October 28, 2010: Senga was drafted as a developmental squad player by the Fukuoka Softbank Hawks in the 2010 Nippon Professional Baseball draft with Takuya Kai and Taisei Makihara.

On May 5, 2023, the general public — and the rest of the National League — got its first glimpse of Kodai Senga in person. In his two-inning Grapefruit League debut against the Cardinals, Senga pumped fastballs at 98 mph, unleashed a couple of trademark forkballs, and limited St. Louis to a run on two hits and two walks.

“He’s good, man,” said Nolan Arenado, who flied to right against Senga in the first inning. “Good fastball. Thought the slider was really good. Obviously he was a little erratic in that first inning, but he seems like he’s got plus stuff and it seems like he’s going to be really good for them.”

Senga is starting from a lower baseline than everyone here but Ohtani — and Ohtani barely pitched in his first three years in the majors, thanks to Tommy John surgery. Part of Senga’s lower innings count was a slightly shorter 2020 season in Japan, but he’s missed time with injuries throughout his career. Since becoming a full-time starter in 2016, Senga has averaged just under 150 innings per season. (Britton - Mar 6,2023 - TheAthletic)

MLB debut - April 2, 2023: Kodai Senga struck out eight in his major league debut, wearing a glove with an image of a ghost and a pitchfork in reference to his "ghost forkball," leading the New York Mets over the Miami Marlins 5-1.

July 8, 2023: MLB announced that Senga would replace Marcus Stroman at the All-Star Game.

TRANSACTIONS

Senga is a 6 ft 2 in, 198-pound right-handed pitcher. With a three-quarters delivery he throws a fastball averaging 95-96 mph that tops out at 100 mph. He has a deceptive forkball, a cutter, and a slider. Due to the effectiveness of his forkball, the pitch has been nicknamed "ghost fork(ball)" in Japan.

2011 to mid-2012 Season:  He played in informal matches against Shikoku Island League Plus's teams, other amateur baseball teams, and played in the Western League of NPB's minor leagues.

2013 season: He tied the Pacific League record of consecutive no-run innings (34.1 innings) by a relief pitcher. On July 19, he participated in the All-Star Game for the first time in MAZADA All-Star Game 2013. On September 4, he left the team with a strain on his left flank and spent the rest of the season rehabilitating.

Senga recorded 51 Games pitched, a 1–4 record, a 2.40 ERA, 17 Holds, one save, and 85 strikeouts in 56.1 innings.

2014 season: Senga pitched as a reliever, but on June 15 he hurt his right shoulder and spent the rest of the season rehabilitating his right shoulder. He finished the regular season with a 19 Games pitched, a 1–1 record, a 1.99 ERA, 3 Holds, and 28 strikeouts in 22.2 innings.

2015 season: Senga pitched in the Pacific League in August, partly due to the rehabilitation of his right shoulder. On August 19, he got his first win as a starting pitcher, finishing the regular season with 4 Games pitched, a 2–1 record, a 0.40 ERA, and 21 strikeouts in 22.1 innings.

In the 2015 Japan Series against the Tokyo Yakult Swallows, he pitched in relief in Games 3 and 4.

 2016 season: Senga pitched as a starting pitcher, and finished the regular season with 25 Games pitched, a 12–3 record, a 2.61 ERA, and 181 strikeouts in 169 innings. The 12 wins in the regular season were the most wins for a pitcher drafted as a developmental squad player and became an NPB record.

2017 Season:  He finished the regular season with a 13–4 record, a 2.64 ERA, 151 strikeouts in 143 innings. And he won the Pacific League Winning percentage Championship (.765 Winning percentage).

In the 2017 Japan Series against the Yokohama DeNA BayStars, he was the first pitcher from the developmental squad player to pitch as a starting pitcher in the opening game. Senga and Kai's battery were the first to win the Japan Series as players who were drafted as developmental squad players.

2018 Season: In the opening game of the season against the Orix Buffaloes on March 30, 2018, Senga pitched his first Opening Day game as a starter. On August 17, in the match against the Orix Buffaloes, he achieved his first shutout game.

Senga finished the regular season with 22 Games pitched, a 13–7 record, a 3.51 ERA, and 163 strikeouts in 141 innings. In the 2018 Japan Series against the Hiroshima Toyo Carp, he pitched in Game 1 and Game 5 as a starting pitcher and contributed to the team's second consecutive Japan Series championship, as well as their 4th in 5 years.

2019 Season: Senga attempted unsuccessfully to get the Hawks to post him to Major League Baseball. The Hawks are the only NPB team to have never posted a player since the posting system was implemented in 1998.

On July 12, 2019, Senga participated in the All-Star Game for the third time. On September 6, 2019, he pitched the second no-hitter in Hawks history, the first no-hitter for the Hawks since 1943. 

Senga finished the regular season with 26 Games pitched, a 13–8 record, a 2.79 ERA, and 227 strikeouts in 180.1 innings. In the 2019 Japan Series against the Yomiuri Giants, he was the winning pitcher in Game 1 and contributed to the team's third consecutive Japan Series championship.

On November 26, Senga was honored for the Pacific League strikeout leader Award, Mitsui Golden Glove Award, and Pacific League Best Nine Award at the NPB AWARD 2019.

2020 Season: Senga finished the regular season with 18 Games pitched, a 11–6 record, a 2.16 ERA, and 149 strikeouts in 121 innings.

In the 2020 Japan Series against the Yomiuri Giants, he has pitched as a starting pitcher in the opening game of the Japan Series for the fourth consecutive year, being the first pitcher to do so since Tsuneo Horiuchi, and became the winning pitcher with no runs in seven innings, contributing to the team's fourth consecutive Japan Series championship.

Senga topped the Pacific League in Win–loss record, ERA and strikeouts and was honored at the Pacific League for the Most Wins Champion Award, Pacific League ERA leader Award and Pacific League strikeout leader Awars at the NPB Awards 2020 on December 17. He also won his second Best Nine Award and Golden Glove Award for the second consecutive year.

Following the conclusion of the 2020 season, Senga once again failed to get the Hawks to post him, instead obtaining a 100 million yen raise for the 2021 season.

2021 Season: Senga was once again marred by injuries in 2021 as the Hawks failed to make the postseason for the first time since 2013. However, he still managed a 10-3 record in 13 games pitched, a 2.66 ERA, and 90 strikeouts in 84.2 innings pitched.

In the offseason, he signed a five-year extension with an opt-out clause after the first season of the contract. So Senga would obtain International Free Agent rights following the conclusion of the 2022 season.

2022 Season:  Senga had the best season of his career, going 11-6 in 22 games pitched, a personal best 1.94 ERA (as a starter), and 156 strikeouts in 144 innings pitched as the Hawks returned to the postseason but lost the Pacific League pennant to the Orix Buffaloes via tiebreaker.

In the 2022 Pacific League Climax Series, Senga once again proved to be an incredibly valuable piece of the Hawks pitching rotation, pitching 12 scoreless innings in 2 starts, helping propel the Hawks past the Lions in the First Stage and preventing the Hawks from getting swept by the Buffaloes in the Final Stage. Following the conclusion of the Pacific League Climax Series, Senga formally announced his intentions to exercise his international free agent rights and head to Major League Baseball in 2023.

Dec 11, 2022: Senga, who turns 30 in January, spent 11 seasons in Japan’s Nippon Professional Baseball organization, all for the Fukuoka Softbank Hawks. Overall, the right-hander posted a 2.59 ERA and 1.12 WHIP over 1,089 innings, striking out 28% of the batters he faced, but also walking 9%. In 2022, he had a 1.89 ERA and a 1.04 WHIP over 148 innings for the Hawks.

During the 2017 World Baseball Classic semifinals, Senga pitched two innings of relief against Team USA, striking out five. Eric Hosmer, Andrew McCutchen, Buster Posey, Giancarlo Stanton and Christian Yelich all went down on strikes against the then-24-year-old. (A DiComo - MLB.com - Dec 11, 2022)

The 6-foot, 178-pound Senga, who features a 101 mph fastball and a biting splitter, filed for international free agency on Oct. 31, and he was recently declared an international free agent. According to FanGraphs, Senga’s fastball has “exploding” action. But his two breaking pitches—a cutter and a slider—are not as effective as the fastball and splitter, particularly when it comes to missing bats.

Senga was not subject to the NPB posting process because he accrued enough service time in the league to file for international free agency. As a result, there is no “release fee” to be paid to his NPB team in order to sign him to a Major League contract.

Adding Senga bolsters a Mets rotation that earlier added free agent Justin Verlander, who will pair with co-ace Max Scherzer. The Mets also signed Jose Quintana and finalized deals with David Robertson and Brandon Nimmo, spiking their payroll well over $300 million. The Mets are likely to enter 2023 with the largest payroll in Major League history. (A DiComo - MLB.com - Dec 11, 2022)

MLB debut - April 2, 2023: Kodai Senga dazzled in his major league debut for the New York Mets Sunday in their 5-1 win over the Miami Marlins. The highly touted Japanese star did not disappoint, going 5 ⅓ innings, while giving up one earned run and striking out eight. 

His mastery of changing speeds and hitting locations from pitch to pitch along with the introduction of his "secret pitch" had Marlins hitters scratching their heads all day.

Senga’s key to success lies within his ability to baffle hitters with his secret pitch: the “ghost fork.”  What exactly is the “ghost fork”? That depends on whom you ask. 

Mets manager Buck Showalter refuses to call it a forkball. Marlins catcher Jacob Stallings chimed in after Sunday’s game in which he went 0-for-2 with one strikeout. 

“It’s tough to pick up,” Stallings said. “He struck me out on a splitter, whatever you want to call it.” 

Whatever you do want to call it, it is nasty, and it is quickly grabbing the attention of the baseball world. (Alex Adrian)

What is Kodai Senga's 'ghost fork?'The hilarious thing about Senga's ghost fork is that no one seems to know exactly how to classify it.

In a sport that loves order, the pitch is chaos. Baseball Savant doesn't quantify its spin on the forkball section of the page. It doesn't show its break under Senga's pitch breakdown. How do you even quantify a pitch with this kind of variance?

The simple answer is that Senga's ghost fork is a forkball that stays looking like a fastball before it reaches the point of no return for a batter, at which point it floats. It might float into the lower part of the zone, it might float into the dirt. But the name comes from the disappearing act it does as it nears home plate. (Kevin Skiver - April 3, 2023)