Groome's relationship with the game was built around his relationship with his father, also named Jason Groome. The two started playing catch together when Jason was five. The Groome men are very close.

“He taught me pretty much everything I know how to do on the field and most importantly how to be a man off the field,” the younger Groome says.

Jason Sr. was an athlete too, wrestling and playing football and baseball growing up. But he didn’t have the same opportunities his son has had, opportunities his son seized.

Groome attended the IMG Academy in Florida in 2015, his junior high school season. And the training really enhanced Jason's development. His parents agreed with their son, that he would receive elite training at IMG.

Asked why he wanted to go to make the move to the IMG academy, he said “I wanted to get my mind and body where it needed to be…I wanted to get bigger stronger and faster,” and he has done just that.

But he chose to return home to Barnegat, New Jersey for his senior high school season (2016), with a commit to Vanderbilt.

“Mostly because I just want to be with my friends and my family before the draft or going to college,” Groome said in an interview in July of 2015.

Rumors circulated around Groome. His decision to leave IMG has raised eyebrows, despite his comments about wanting to be with his family. His confident attitude has rubbed some baseball people the wrong way. He pitched at USA Baseball’s Tournament of Stars but also left the event early, missing a second scheduled outing, and was left off the 18U National team roster.

However, coaches who have had Groome say he’s consistently shown up on time and done his work. He’s supported his teammates; after pitching at the Area Code Games, Groome stuck around for the rest of the week, embracing the team culture that the Area Code Games coaching staffs encourage.

When asked what he plans to study if he attends Vanderbilt, he said “I want to be become a teacher, so down the road I can become a coach."

Groome’s first two starts of the season—one of which was the first no-hitter in Barnegat’s history—were erased from the record books, and the team had to forfeit both of those games. A public relations person from the NJSIAA said that the organization became aware of Groome’s rule violation after his no-hitter. Even those who have had their doubts about Groome’s makeup were sympathetic to the ineligibility ruling; after all, he announced last summer that he was returning to Jersey.

Jason is confident, yet soft-spoken.

Groome organizes his time well, concentrating on things that aid his pitching career. For example, at the Area Code games during the summer of 2015.

"Let me tell you something about Jason,” began Matt Hyde, a Northeast area scout for the Yankees and longtime coach of the organization’s Area Codes squad. He’s seen several future major league stars come and go at the games.

“Jason Groome has stayed here the entire week,” he said, “which tells you a lot about him.”

In this day and age of social media and increased exposure, blue-chip prospects are often on their own schedule, even at the high school level, bouncing around from showcase to showcase. They don’t always show up to team events; they play and move on.

“Usually they throw and they leave, and they go on to the next thing,” Hyde said, on the penultimate day of the upper-class games. “(Groome) stayed. He’s in the bullpen.

“I had him get the helmet bag today, you know?” he said, laughing. “That sort of thing is great.”

That sort of thing defines Groome. It’s not that he isn’t career-conscience. He is. That’s what motivated him to leave his hometown school of Barnegat High and head to the star-making, prospect-grooming IMG Academy in Bradenton, Fla., for his junior year. It was there that he packed on weight and reinforced his frame.

But, more than anything, Groome loves playing baseball. He’s a gamer. That’s what stood out most to Hyde during the Area Codes process. And, ultimately, that’s what motivated Groome, a Vanderbilt commit, to leave IMG and head back to Barnegat for his upcoming senior season.

“I wanted to graduate with my friends,” Groome said. “And my friends are telling me they want to win a state championship with me, so that’s what we’re going for, so we can get it done.” (Michael Lananna - Baseball America - 9/04/15)

Groome is young and gifted. His non-baseball interests are limited. He likes hanging out with his friends, shooting hoops and going fishing. “When I don’t have practice on a Sunday or I get home from early practice, I just go out to the lake and catch some fish,” he says. “I mean it doesn’t really get my mind off of baseball that much.”

The Red Sox chose Groome #1-June, 2016 -- the 11th player chosen overall.  July 15, 2016:  Jason is an official member of the Red Sox after signing a $3.65 million contract, via scout Ray Fagnant.

Jason, who was a high school senior just a few months previous, was a bit awestruck by his surroundings.  Groome had already been to Fenway Park a couple of months previous just before he signed with the Red Sox.

But this time he was there on a gameday -- Red Sox-Yankees no less. From the clubhouse to the manager's office to the field itself during batting practice, this was the best field trip of Groome's 18-year-old life.

"Just being out here and being on my professional ballclub's field, shagging with all the big leaguers, I mean, it was just a great experience and actually meeting them," said Groome. "I was talking to [Rick] Porcello out there and I just said, 'It's so weird just meeting you guys, from watching you guys on TV, just finally meeting you guys face to face."'

Groome also got to meet someone who he will never get a chance to play with in David Ortiz, who will retire at the end of the 2016 season.  "I was just shell-shocked, because I was watching him since I was 6 or 7 [years old] probably," said Groome.

The chance to talk to Porcello was particularly meaningful, because they are both New Jersey natives. Porcello was drafted with the 27th overall pick out of high school in 2007 and was in Detroit's starting rotation within two years.  "He told me to trust the process," Groome said of the advice Porcello gave him.

Several family members accompanied Groome for the trip to Fenway.

"Yeah, this is only my second time here, but, I mean, it still feels like it's a dream," Groome said. "I never thought I would be playing for the Red Sox and really just having my family up here, it's their first time in Boston. Just a great feeling."

What does Groome feel his most immediate need of development is?  "Mainly my command of my changeup," Groome said. "I really didn't throw it too much in the spring my senior year. I threw it a couple times in the GCL, threw it a couple of times in Lowell. I've still got to focus on the command of it, and that's what I'm going to work on."  (Browne - MLB.com - 9/16/16)

The Baseball America Prospect Handbook rated Groome as the 5th-best prospect in the Red Sox organization in the spring of 2017. They moved him up to #1 a year later, early in 2018.

After missing the book in 2019, because of Tommy John surgery, Jay was at #7 in the spring of 2020, and at #6 in 2021. He was at #10 in the spring of 2022. And he was at #8 early in 2023.

Q&A: Red Sox MassLive.com beat reporter Christopher Smith interviews prospect Jason Groome: March 2017

Smith: You have a big family, right?

Groome: Yeah, it's pretty big. My oldest sister (Ashleigh), she's a teacher. She graduated college two years ago. Penn State. My second sister (Kaitlyn), she recently just had a baby. So I've got my first nephew. And then I have two crazy twin brothers who are 4 years old.

Smith: What do you like to do outside of baseball?

Groome: I used to be a big hoops player. I used to play but stopped after my sophomore year. But every chance I get to get back out on the court and just shoot around, I love that.I have a place down here. So I fish all the time. I fish right in my backyard. I did that a lot when I was in Jersey, too -- just fished a lot. That was one of me and my dad's hobbies. Me and buddies, we always go out on the lakes and just hope for something big.

Smith: What was your first big purchase after you signed your first pro contract?

Groome: I always was into Mercedes. And I did a lot of looking to pick out the right one. Yeah, I purchased my first vehicle a couple months after. It was a Mercedes C63 S AMG, 2017. So I got my dream car that I always wanted. And I actually purchased mother a car, too, for Christmas.Smith: What kind?Groome: I got her a Chevy Suburban because she likes big trucks like that.

Smith: Anyone else in your family play sports?

Groome: Yeah (nobody played beyond high school). My mom was a basketball player. My dad played pretty much all sports: hockey, football, soccer. He wrestled. Baseball, basketball.My oldest sister is a big basketball player, too. And then leaned more towards dancing. And then she followed her path with teaching because that's what she wanted to be. My sister Kaitlyn, the middle one, she was a big basketball player, too. I guess just never followed through with it after high school either. She wants to become a police officer. So I mean, that's a good career to get her into.

Smith: Who has taught you the most?

Groome: My father. I can honestly say he was he was my coach ... Everything that I learned: my mechanics, my delivery, how I throw the ball, almost every pitch, is from my father. If you ever get the chance to ask him he's going to say, "I saw it in him, and I just pushed him to be the best."

Smith: How did he know how to teach all that? Did he pitch?

Groome: Yeah. He said he was a third baseman/pitcher. But he's a righty and I'm a lefty. I have this video of me throwing when I was like 5 or 6 years old. And finally saw it because my grandma showed me it. And I was like, "Wow. I looked that good throwing?" (My dad) was like, "Yeah. It would have to take someone that doesn't know anything about baseball to know you weren't ever going to be this good."

During the summer of 2017, Groome's father was arrested on drug and weapons charges. That was rough.

Jay really impressed Red Sox brass for the strength and conditioning work he did over his rehab from Tommy John. 

2020 Season: The Red Sox sent him to their alternate training site in 2020 to get innings, and he held his own against more advanced hitters while offering a reminder of why he’d been so highly-regarded as an amateur. 

July 15, 2021: Groome and his wife Amanda welcomed their daughter, Londyn Rae, into the world.

 June 4, 2024: Groome was one of four players suspended for at least one year for betting on baseball. This also included wagers placed on Boston’s major league team while he was a minor leaguer in the organization in 2020 and 2021.

Groome in the Padres system, is now banned from the league for one year for violating MLB’s sports betting rules and policies.

TRANSACTIONS

Groome has a 92-96 mph 4-seam FASTBALL (that is a 55 grade), an 88-93 mph 2-seam SINKER that he consistently places down and to his arm-side. He gets excellent spin/tight rotation on his devastating 77-79 mph two-plane CURVEBALL with plus bite and deep 1-to-7 break -- getting a 50 grade. He has decent feel on his 50 grade CHANGEUP, which he spots down in the strike zone and, when sequenced properly, can miss righthanded bats. And he also has a CUTTER/SLIDER that has a 50 grade. Jay has 50 grade Control.

Jay's stuff never fully bounced back after surgery, Groome is more of a pitchability lefthander than someone who overwhelms hitters. His fastball sits 90-94 mph and can touch 95-96. He commands the pitch to all quadrants of the zone and has added a two-seamer and an average cutter. His formerly elite curveball is more horizontal these days than a true north-south biter, but it is still average.

Groome has ballooned from 220 to 262 pounds, so his conditioning and stamina are issues the Padres would like addressed. He often dominated early only to fall apart after a few innings, so it was a step in the right direction for him to complete eight innings for the first time after arriving in El Paso. He has reverse platoon splits and dominates righthanded hitters while struggling against lefties. (Jeff Sanders - Baseball America Prospect Handbook - Spring, 2023)

Groome's fastball velocity isn't what it once was, as he now operates in the low 90s and usually touches 94-95 mph only for an inning or two at a time. His best pitch is a mid-80s slider that he refined at Boston's alternate site in 2020, as it now shows flashes of becoming a plus offering and has surpassed his upper-70s curveball, which scouts considered the best bender in the 2016 Draft. He has developed a low-80s changeup with tumble that helps him handle right-handers, who fared far worse against him (.619 OPS) than same-side hitters (.890) in 2021. 

Evaluators aren't sure exactly what to make of Groome, who has puffed up to a listed 262 pounds and is less athletic than he was as an amateur. He throws strikes but might find more velocity and consistency if he got into better shape. He’ll try to show San Diego that he can still be a potential No. 5 starter in his second organization, but it might not be long before the Padres give him a look in the bullpen. (Spring 2022)

Groome has ballooned from 220 to 250 pounds, and his conditioning and stamina are issues. He often dominates early in outings only to fall apart after a few innings. He has reverse splits and dominates righthanded hitters while struggling against lefties. (Alex Speier - Baseball America Prospect Handbook - Spring, 2022)

Jay was added to the 40-man roster in November, 2020.  Scouts considered his curveball the best in the 2016 Draft, but it's more of a solid offering now and has been surpassed by his slider, which has gained velocity since he added it in 2020. He has developed more confidence in his sinking changeup, which can become an average offering.

Known for using his athleticism and clean delivery to pound the strike zone as an amateur, Groome needs to keep his conditioning in check to locate his pitches where he wants. Boston still sees the ingredients of a quality starter and hopes that his finally getting regular innings in 2021 will help him reach that potential. (Spring 2021)

Jay is developing into a lefthanded mid-rotation starter, including a powerful build, a controlled, repeatable delivery and giant hands that allow him to manipulate the ball. The deception in his delivery resulted in lots of whiffs on fastballs at the alternate site in 2020.

Groome has regained the velocity on his fastball with some arm-side run. He also shows flashes of what scouts rated the best curveball in the 2016 Draft, a well above-average bender with power and depth, though he's still seeking consistency with it. He developed more confidence in his sinking changeup during his rehab process and it could become a solid third offering. Jay has a natural ability to manipulate the baseball. 

Though he battled his control before he got hurt, Groome has the athleticism and clean delivery to provide consistent strikes. He uses his 6-foot-6 frame to create angle and plane on his pitches, helping keep them off barrels. Boston still sees a potential frontline starter and hopes he'll finally take steps toward becoming one in 2020. (Spring 2020)

2020 Season: Left-hander Jay Groome obviously needs innings. MLB Pipeline's top-rated prospect in the 2016 Draft has worked just 75 frames (counting the playoffs) since signing him and missing time with a lat strain, forearm soreness and Tommy John surgery. But the Red Sox view his stint in instructional league as more than just an opportunity to get him on the mound.

"We're absolutely working on pitch development and his delivery and routine and things like that," Boston farm director Ben Crockett said. "The fact that he was able to finish last year, that was really big, and then he got to pitch in instructional league last year and start up in Spring Training and join our alternate site. So there's been more development than his innings would dictate.

"His velocity has been good, sitting at 92-96 mph. He's always commanded his curveball and had good feel for it. He continues to work on his changeup as a third pitch and recently introduced a slider." (J Callis - MLB.com - Oct 30, 2020) 

Jason says he started throwing his tight curve when he was 14, taught the grip by a friend on his travel ball team.

“It just clicked after the first couple of times I started throwing it in the bullpen,” Groome said. “And ever since then, I just mastered it.”

Groome likes to use that curve as a chase pitch, for the most part -- down and to his glove side, though he will backdoor it to a righthanded batter for a strike.

Many scouts say Jay's curveball is a 60-grade pitch. Some feel it could be even better. His curve is unhittable, especially vs. lefthanded batters. Groome also throws a changeup that has occasionally flashes above-average potential with its tumbling action. Jason said it’s a pitch he continues to work on, but it can be easy to pocket when his fastball and curve are on. (Spring, 2018)

Jason is a lefthander who works from the third base side of the rubber so that he can get cross-plate action. It is an easy delivery. And he has the excellent ability to manipulate the baseball.

"It helps me pound the inside corner and when I throw my two-seamer or running fastball it cuts across the plate to get inside to the lefty…I get a lot of movement on the ball when I am toward the right side of the rubber”.

Groome has a clean arm action, and easy delivery. He repeats it consistently. He is a pretty advanced lefthander. His delivery may remind you of Jon Lester or Andy Pettite. Jason throws "comfortable heat."

He can easily throw his heater down and to either corner of the plate.

More on Jason's curveball: The spin on Groome's curveball is extraordinarily tight, a result of Groome’s hand speed. As he matures and navigates his way through the minor leagues, Groome will look to add consistency to the pitch. When he throws it now, he can sometimes get underneath the pitch, causing it to move upward before its downward snapping motion. That upward movement could tip off better hitters. When Groome is on top of his curveball, however, it’s already a plus pitch.

Jason had toyed with a curveball, but really found his grip in the summer 2012, playing at the Elite 32 World Series. He took notice of one of his teammates’ curveballs, a 12-to-6 hammer that his friend Shane had thrown.

“I could never really throw a curveball just having my fingers like across the horseshoe, and I tried spiking it when I was throwing in the bullpen,” Jason said. “By the second pitch I just had feel for it and I threw it the rest of the tournament when I pitched. I brought it back my sophomore year and I just mastered it from there.” (Hudson Belinsky - Baseball America - 5/06/16)

Jason is going to be a solid #2 or #3 starter.

“I’m extremely excited for Jay Groome,” said Triple-A pitching coach Paul Abbott. “We asked him to intensify his bullpens and side sessions. He did. Introduced some slight adjustments to the mechanics, get his legs more involved, get some better extension on his fastball. He’s got more confidence in his breaking ball. He said since the surgery, it’s the best he’s felt trusting the effort with it.

“He’s got this bounce in his step and he comes to work every day. I told him today, ‘I’m extremely impressed with the way you’re going about your business. You’re looking like a big leaguer – like you want to be there.’ The ball is coming out really well. He’s throwing hard. He’s commanding all his pitches. As of now, he’s showing signs of a really solid, strong, three-pitch mix. It’s pretty impressive.”  (Browne - mlb.com - 8/21/2020)

2020 Season: LHP Jay Groome, MLB Pipeline club ranking: No. 7, 2021 Opening Day Age: 22, MLB ETA: 2022

Injuries have limited Groome to 66 low-level innings since the Red Sox took him No. 12 overall in the 2016 Draft, signing the left-hander for a franchise-record $3.65 million. Protecting him now ensures Boston doesn't lose out on that investment and prevents another team from stashing Groome in a big league bullpen for a full season. It wouldn’t have been unreasonable for a club to toy with the idea: the 6-foot-6 southpaw features a mid-90s heater, a plus curveball and considerable prospect cache, despite his injury history.

2021 Season: The 2016 first-round pick did not come out of the gates on fire. After three starts, Groome's ERA was an unsightly 14.73 with High-A East opponents knocking him around to the tune of a .405/.500/.730 slash line. With that for context, Groome's season-ending 4.81 ERA looks quite a bit better. The big left-hander posted an even 4.00 ERA from that point on, allowing just a .221 batting average and leading the system with 134 strikeouts. His season peaked with his promotion to Portland in September, as he introduced himself to Double-A by allowing just four hits in 11 scoreless innings while striking out 19 in his first two starts.

2022 Season: Coming over from Boston in the Etic Hosmer trade, there is some upside to this lefty. Groome has started his whole career where he features a four-pitch mix. His fastball sits in the mid-’90s, and his out pitch is a tight slider. Tommy John surgery and other nagging injuries have limited him, but he does own a 4.25 ERA over 300 plus minor league innings. Groome has yet to make his major league debut, and there is a good chance you will see him in 2023. He may benefit from Niebla and a full spring working with his new pitching coach.  (James Clark - Nov. 5, 2022)

April 11, 2017: Groome was on the DL with a minor lat strain.

August 23, 2017: Jay was on the DL with minor forearm soreness.

April 5, 2018: Groome was on the DL with a flexor strain in his left elbow.

May 15, 2018 : Groome underwent Tommy John surgery.

2019: Jay was on the IL most of the season, rehabbing from the TJ surgery.