Ranking the Top 5 Japanese Players in Boston Red Sox History

With the Los Angeles Dodgers and Chicago Cubs set to face off in the Tokyo Series, there is no better time to recognize the importance of Daisuke Matsuzaka, Koji Uehara, Masataka Yoshida and other Japanese players in the Boston Red Sox history books.

Boston, MA, USA; Boston Red Sox relief pitcher Koji Uehara is lifted by designated hitter David Ortiz after Game 6 of the MLB baseball World Series against the St. Louis Cardinals at Fenway Park. The Red Sox won 6-1 to win the series four games to two. / Robert Deutsch-USA TODAY

For the first time in six years, MLB is returning to Japan.

The Los Angeles Dodgers and Chicago Cubs are set to face off in the much-anticipated Tokyo Series at the one and only Tokyo Dome, which has played host to 10 big league games in the past. This will mark the Dodgers' first time playing in the 55,000-seat stadium, while the Cubs are returning for the first time since 2000.

Between Shohei Ohtani, Yoshinobu Yamamoto, Roki Sasaki, Seiya Suzuki and Shota Imanaga, there will be no shortage of Japanese stars taking the field when Los Angeles and Chicago face off.

The Dodgers and Cubs aren't the only MLB teams that have attracted premier Japanese talent, however. The Boston Red Sox, for instance, have had nearly a dozen players come over from Japan over the years, trailing only the Dodgers, New York Mets and Seattle Mariners in that regard.

Whether it's been the can't-miss stars, one-hit wonders or the late bloomers, a handful of those Japanese players have helped the Red Sox win multiple titles.

Here is a ranking of the best Japanese players ever to wear a Red Sox uniform:

Honorable Mentions

Boston, MA, USA; Boston Red Sox former player Dave Roberts is introduced prior to throwing out the first pitch in Game 2 of the American League Championship Series baseball game against the Detroit Tigers at Fenway Park. / Bob DeChiara-Imagn Images

Dave Roberts: Roberts, born in Japan to a Japanese mother, was never a superstar. He played just 45 regular season games with the Red Sox, recording a mere 0.3 WAR in that time. But by stealing second base in the ninth inning of Game 4 of the 2004 ALCS, Roberts established himself as a folk hero in Boston for years to come. If it wasn't for his clutch baserunning, the team wouldn't have come back from down 3-0 to upset the New York Yankees, nor would they have broken the 86-year Curse of the Bambino.

Tomo Ohka: While his big league numbers don't jump off the page, Ohka was the first Japanese player ever to suit up for the Red Sox. He went 3-6 with a 3.12 ERA and 2.3 WAR across 13 appearances in 2000, but had negative WARs in 1999 and 2001. Ohka did go 18-11 with a 3.02 ERA with Triple-A Pawtucket, though, appearing in the All-Star Futures Game twice.

Hideo Nomo: A trailblazer for Japanese players heading to MLB, Nomo spent one year with the Red Sox in between his more successful stints with the Dodgers. He led the league with 220 strikeouts in 2001, going 13-10 with a 4.50 ERA, 1.348 WHIP and 3.1 WAR.

5. Masataka Yoshida, OF/DH (2023-Present)

Houston, Texas, USA; Boston Red Sox designated hitter Masataka Yoshida (7) steals second base against the Houston Astros in the seventh inning at Minute Maid Park. / Thomas Shea-Imagn Images

The Red Sox took a big swing when they inked Yoshida to a five-year, $90 million contract in December 2022. He proceeded to finish sixth in AL Rookie of the Year voting right off the bat, putting up a .289 batting average, 15 home runs, 33 doubles, 72 RBIs, eight stolen bases, a .783 OPS and a 1.4 WAR across 140 games in 2023.

Yoshida was banged up and hardly saw any time on defense in 2024. He was limited to 108 games by thumb and shoulder injuries, batting .280 with 10 home runs, 21 doubles, 56 RBIs, two stolen bases, a .765 OPS and a 1.4 WAR as a designated hitter.

If the front office is unable to trade Yoshida and his contract this season, he is likely to finish the year with more games played than any other Japanese player in Red Sox history. His .775 career OPS ranks fourth-highest among Japanese-born MLB players, trailing only Ohtani, Seiya Suzuki and Hideki Matsui, while his .285 batting average ranks second to Ichiro.

4. Junichi Tazawa, RP (2009-2016)

Boston, MA, USA; Boston Red Sox relief pitcher Junichi Tazawa (36) during the eighth inning against the Minnesota Twins at Fenway Park. / Winslow Townson-Imagn Images

Tazawa was far from a star when he signed with the Red Sox in 2008, having never even played professionally in Japan to that point. He made his MLB debut at age 23 in 2009, but underwent Tommy John surgery in 2010 and was transitioned to the bullpen when he returned in 2011.

The Red Sox gave Tazawa a real shot in 2012, and he took advantage by posting a 1.43 ERA, 0.955 WHIP and 1.7 WAR in his 37 appearances.

Tazawa took the mound 142 times between 2013 and 2014, ranking seventh in the AL during that span. He remained effective as his workload grew, too, going 9-7 with a 3.02 ERA, 1.195 WHIP and 1.7 WAR.

During the 2013 World Series run, Tazawa appeared in 13 of the club's 16 postseason games, posting a 1.23 ERA and 0.955 WHIP.

Tazawa's ERA exceeded 4.00 in both 2015 and 2016, but he still had positive WARs and remained a mainstay in Boston's bullpen. By the time he retired, he ranked third all-time among Japanese pitchers in career MLB appearances with 388.

3. Hideki Okajima, RP (2007-2011)

Cleveland, OH, USA; Boston Red Sox pitcher (37) Hideki Okajima delivers a pitch against the Cleveland Indians during Game 3 of the 2007 American League Championship Series at Jacobs Field. / Tom Szczerbowski-Imagn Images

Okajima burst onto the scene as a dominant reliever when he joined the Red Sox in 2007. He made an All-Star appearance mere months into his MLB career, capping off his debut campaign with a World Series ring and a sixth-place finish in AL Rookie of the Year voting.

Between 2007 and 2009, Okajima went 12-4 with a 2.72 ERA, 1.125 WHIP, 8.3 strikeouts per nine innings and a 6.7 WAR. He racked up 73 holds across those three seasons to go along with six saves.

Okajima took the mound 17 times in the playoffs during that stretch as well, posting a 2.11 ERA and 0.844 WHIP.

Even once Okajima started to fall off in his mid 30s, he still muscled his way through 56 appearances in 2010. Only four other Japanese relievers have appeared in more MLB games than Okajima, while only three have a lower career ERA.

2. Koji Uehara, CL (2013-2016)

St. Petersburg, FL, USA; Boston Red Sox relief pitcher Koji Uehara (19) against the Tampa Bay Rays at Tropicana Field. / Kim Klement-Imagn Images

Uehara had already strung together a decently successful big league career by the time he joined the Red Sox. Over his four seasons with the Baltimore Orioles and Texas Rangers, the righty put up a 2.89 ERA and 6.2 WAR.

But the moment Uehara arrived in Boston, he took his game to a whole new level.

Uehara went 4-1 with a 1.09 ERA, 0.565 WHIP, 12.2 strikeouts per nine innings, 21 saves and a 3.5 WAR in the 2013 regular season, finishing seventh in AL Cy Young voting and 19th in AL MVP voting. He went on to win ALCS MVP that fall, posting a 0.66 ERA, 0.512 WHIP and seven saves en route to a championship ring.

Between his pickoff that ended Game 4, his title-clinching strikeout in Game 6 and his instantly iconic leap into David Ross' arms, Uehara became a living legend during that World Series.

That historically dominant playoff run put Uehara on the map, and he followed it up by making an All-Star appearance in 2014. He remained relevant in 2015 and 2016, ultimately finishing his four-year stint in Boston with a 14-13 record, 2.19 ERA, 0.810 WHIP, 11.6 strikeouts per nine innings, 79 saves and a 7.2 WAR.

1. Daisuke Matsuzaka, SP (2007-2012)

Boston, MA, USA; Boston Red Sox starting pitcher Daisuke Matsuzaka (18) delivers a pitch in the first inning against the Baltimore Orioles at Fenway Park. / David Butler II-Imagn Images

When Boston signed Matsuzaka ahead of the 2007 season, Red Sox Nation went into a frenzy.

It was hard to go anywhere in the city without seeing a "Dice-K" shirt or jersey. Even on a team that featured household names, top prospects or blockbuster additions at nearly every position, Matsuzaka still managed to establish himself as a fan-favorite before ever playing a game.

Matsuzaka didn't disappoint once he finally took the mound, either. He finished fourth in AL Rookie of the Year voting and won a World Series in his first season with the Red Sox, then placed fourth in the 2008 AL Cy Young race.

Through his first two seasons in Boston, Matsuzaka was 33-15 with a 3.72 ERA, 1.324 WHIP, 8.6 strikeouts per nine innings and a 9.5 WAR. The Red Sox went 6-1 across his seven playoff starts as well.

The fact that Matsuzaka went 17-22 with a 5.53 ERA, 1.537 WHIP, 7.7 strikeouts per nine innings and a -0.3 WAR over the next four seasons hardly spoiled fans' appreciation for what he achieved upon his arrival. His stardom also paved the way for a whole new generation of Japanese starting pitchers to join MLB from Hiroki Kuroda and Hisashi Iwakuma to Yu Darvish and Masahiro Tanaka.

Related MLB Stories

• BETTS RULED OUT: Dodgers superstar Mookie Betts will not take the field in the Tokyo Series after all, as he has lost nearly 15 pounds battling an illness. CLICK HERE

• CROCHET NAMED ACE: The Red Sox officially tabbed offseason trade acquisition Garrett Crochet as their 2025 Opening Day starter on Saturday. CLICK HERE

• OHTANI GOES YARD: In an exhibition game against the Yomiuri Giants, Dodgers superstar Shohei Ohtani sent Japanese fans into a frenzy with a home run Saturday. CLICK HERE

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