The second month of the Major League Baseball season saw several Japanese import players continue to make significant contributions. Of the pitchers, Yoshinobu Yamamoto of the Los Angeles Dodgers and Kodai Senga of the New York Mets shone brightly, while the Baltimore Orioles’ Tomoyuki Sugano again made a solid impression, and Yusei Kikuchi of the Los Angeles Angels rebounded from a poor start to have a good May performance.
Shohei Ohtani? He had his usual – ho hum – excellent month as a hitter while getting closer to making a comeback on the mound. Designated hitter Seiya Suzuki of the Chicago Cubs held steady, as did reliever Yuki Matsui of the San Diego Padres.
On the downside, heralded young Dodger pitcher Roki Sasaki, who had exhibited both potential and growing pains, hit the Injured List with a shoulder impingement, as did Shota Imanaga of the Cubs, the latter with a hamstring injury.
Fellow pitcher Kenta Maeda of the Detroit Tigers was designated for assignment, while pitcher Yu Darvish of the Padres and Boston Red Sox outfielder Masataka Yoshida have yet to play because of injuries.
Yoshinobu Yamamoto
In the second season of a 12-year, $325 million contract, Yamamoto has looked like the ace the Dodgers were hoping for. He’s displayed an otherworldly splitter, appears to have improved each of the pitches in his repertoire, and his command has been excellent.
After a solid, if injury-truncated, rookie season, Yamamoto was 6-3 at the end of May after 11 starts, and he sported a 1.96 ERA and 0.91 WHIP. He walked 11 batters while striking out 75 in 64 innings. He also had an 18-inning scoreless streak at one point.
Opposing batters are hitting just .114 off Yamamoto’s splitter and .153 against his four-seam fastball, which have comprised 65 percent of his pitches thus far. In 2024, hitters averaged .170 against his splitter and .260 versus the four-seamer. The barrel rate against Yamamoto is just six percent.
“There’s a lot of time [left in the season], but I do think that right now, [Yamamoto’s] the best pitcher in the National League,” Dodgers manager Dave Roberts said after Yamamoto went seven innings to win a duel with Texas’s Jacob DeGrom.
Dodger catcher Will Smith added that “He’s been really good at going deep into games, especially since we’ve had trouble with starters doing that and staying healthy.”
Kodai Senga
Senga has been outstanding in the early part of the 2025 season in the wake of a 2024 season in which he made just one regular-season appearance because of injuries. Having added a two-seam fastball, or sinker, to his repertoire that includes his deadly “ghost forkball”, he is 6-3 with a 1.60 ERA, and a 3.21 Fielding Independent Pitching (FIP) mark, the latter currently better than in his first two seasons.
He did walk 19 batters in 33.1 innings in May, though, and has walked 4.1 batters per nine innings. Also, his strikeout rate is at 8.6 per nine innings, compared to 10.3/9 in his rookie MLB season of 2023. In 11 seasons in Japan, he averaged 10.0 strikeouts and 3.4 walks per nine innings.
The forkball remains his best out pitch, as batters are averaging just .108 against it. They are also hitting just .167 off his slider, while they’ve had much better luck against his four-seam fastball – a .296 mark.
“(It’s) what people saw here in 2023 — a guy that’s going to take the baseball and he’s going to give you a chance every night,” Mets manager Carlos Mendoza said. “It doesn’t matter who we’re facing. We feel good about our chances when he takes the ball. This is someone that’s going to match the best of the best when he’s healthy and feeling good.”
Shohei Ohtani
The National League’s Most Valuable Player in 2024, when he hit .310 with 54 home runs and a 1.036 OPS, Ohtani averaged .287 during the first two months of this season with 22 home runs and an OPS of 1.045. He has 11 stolen bases, as well, and his hard-hit rate is 62.3 percent, which would be the highest of his career. At the end of May, he ranked second in MLB in home runs.
In May alone, Ohtani averaged .309 with 15 homers, 27 RBI, and an 1.180 OPS.
Time will tell whether he can come close to replicating his batting achievements of 2024, given that he is planning to return to the mound on a regular basis when he fully recovers from his second Tommy John surgery. That could come in June, though there is no official timetable as yet. He had a 29-pitch session against a group of minor leaguers at the end of May, and the signs were hopeful.
“I think he wishes his command would have been a little bit better,” Dodgers manager Dave Roberts said afterward, “But really positive day for Sho.”
Seiya Suzuki
Suzuki has mostly been a designated hitter this season, so far appearing in just five games as an outfielder. His bat, not his defense, is his strong point (though he does occasionally flash good glove work, as one can see in the above video).
After averaging .321 in April, he dropped to .259 in May, though he had a .565 slugging percentage and an. 879 OPS. He also drove in 27 runs during the month and at the end of the month was tied with Boston’s Rafael Devers for the MLB lead with 52.
For the season, he’s hitting .269 with an .895 OPS, 14 home runs and a .562 slugging percentage. At the moment, his slugging percentage, and OPS are ahead of his career marks. His barrel and hard-hit rates are significantly up, as well. In a game against Cincinnati, he hit a home run with an exit velocity of 116.2 mph – the hardest-hit homer by a Cubs hitter since Kyle Schwarber belted one at 117.1 mph on April 24, 2018.
“I don’t know if I can say it’s the best [stretch of my career],” Suzuki said via his interpreter, Edwin Stanberry. “But I feel like I’ve been doing really well. Obviously, I’m going to have moments where the performance isn’t as good, and I’ll talk to the coaches and see what adjustments I need to make. But I’m happy with how it’s gone so far.”
Cubs president of baseball operations Jed Hoyer said, “His ability to hit and to continue to develop hitting premium velocity has been really important,” Hoyer said. “I just see a guy that’s more aggressive both in demeanor and also in counts. He was a little bit more passive at the plate before.”
Roki Sasaki
The 23-year-old phenom’s introduction to MLB had had its ups and downs, and then a right shoulder impingement necessitated a May 14 move to the 15-day Injured List, where he remains. The current target for his return is late June.
Sasaki had two starts in May – against Atlanta on May 3 and against Arizona on May 9 – and he gave up 11 hits, four walks, and eight earned runs in nine innings while striking out just four. Sasaki had felt discomfort in his shoulder those two outings. Speaking through interpreter Will Ireton, he described the initial feeling not as pain, but rather “not the ideal way that I want my shoulder to move.” He did not attribute his lower velocity and command issues to his shoulder. “It’s hard to tell if it’s the main reason why my velo and command was affected,” Sasaki said.
Dodgers manager Dave Roberts said Sasaki’s injury is similar to the shoulder soreness that limited him to just 18 starts and 111 innings last year for the Chiba Lotte Marines in Nippon Professional Baseball.
Sasaki wasn’t healthy throughout any of his four seasons in Nippon Professional Baseball (NPB), and there were questions about how he would avoid injuries in MLB. He has pitched 100 or more innings in a season just twice, and his highest total is just 129.1, so the Dodgers have closely managed his workload.
His velocity dipped last season after going as high as 102 mph previously, and the average velocity on his fastball so far this season is 96 mph, though he’s reached as high as 100.5 on his four-seamer, which he has thrown 50 percent of the time. A splitter and a slider are the only other pitches he’s thrown thus far. Hitters are averaging .253 against the four-seamer, .158 vs. the splitter, and .250 off the slider. Their average against his slider in March and April was just .111.
Sasaki’s season marks show a 1-1 record, 4.72 ERA, and 1.49 WHIP. He’s issued 22 bases on balls in 34.1 innings while striking out just 24. Opposing batters’ hard-hit rate is 43.8 percent.
Shota Imanaga
After a rookie MLB season in which he was 15-3 with a 2.91 ERA and 1.02 WHIP, Imanaga began the new season without missing a beat. However, he was derailed in his first May start, against Milwaukee, when he suffered a left hamstring strain and was placed on the 15-day Injured List. He injured the leg while running to cover first base in the sixth inning.
“The most important thing with that kind of injury,” Cubs president of baseball operations Jed Hoyer said, “is to get him back and healthy for the remainder of the season, not just to get him back. You talk about returning to play, versus returning to your previous form. That’s the most important thing, and it may take some time to get there.”
Imanaga went 5.2 innings against Milwaukee, allowing four hits and two earned runs. He took the loss in that game and currently has a 3-2 win-loss mark, 2.82 ERA, and 1.10 WHIP.
Imanaga was the first pitcher to go seven innings in a game twice this season.
The only blemishes so far are that Imanaga’s walk rate is nearly double what it was in 2024 (2.8 per nine innings vs. 1.5/9) and his strikeout rate is down (6.8 per nine innings vs. 9.0/9). Opposing hitters’ barrel rate is slightly higher, but their hard-hit percentage is virtually the same.
Tomoyuki Sugano
In his first MLB season at age 35 after 12 seasons in Nippon Professional Baseball (NPB), Sugano has been solid thus far.
In his first month in MLB, he made six starts, posting a 3-1 record and 3.00 ERA. He followed that with a 1-2 mark and 3.48 ERA in May, and his WHIP improved to a very low 0.97. He walk rate has been very low, as well – just four bases on balls in 31 innings in May and 10 in 64 innings for the season. His season line at the end of May was 4-3 with a 3.23 ERA and a very good 1.06 WHIP.
Sugano is also giving the Orioles some innings, going at least six innings in four of his five May starts and 5.1 in the other.
He was not known as a strikeout pitcher in Japan, averaging 7.7 per nine innings there, but that has fallen steeply in his first foray into MLB. His strikeout rate currently is 4.92 per nine.
Interesting article here on Sugano and his journey to MLB.
In 12 seasons with the Yomiuri Giants, Sugano posted a 136-75 record with a 2.43 earned-run mark and 1.035 WHIP. He twice won the Sawamura Award – Japan’s equivalent of MLB’s Cy Young Award – and was an eight-time all-star.
Yusei Kikuchi
Kikuchi, perhaps somewhat surprisingly, chose the Los Angeles Angels in free agency, signing a three-year, $63 million contract in late November 2024, despite a history of inconsistency.
Kikuchi had good results from spring training, with the addition of a sweeper to his repertoire making a big difference. After an inconsistent April in which he was 0-4 in six starts with a 4.31 ERA and bloated 1.60 WHIP, he turned it around in May. In his six starts, he was 1-1 with a 1.89 ERA, though he did walk 17 batters (three intentionally) in 33.1 innings.
For the season, he is 1-5 with a 3.06 ERA and a 1.52 WHIP.
A couple of worrisome stats are that, compared to last season, his walk rate is up and his strikeout rate is down. On the other hand, his hard-hit rate is significantly lower – better at this point than in the previous four seasons.
Yuki Matsui
Matsui, a 29-year-old in his second MLB season, was solid for the Padres in May until his last outing when he failed to get an out against Pittsburgh while allowing four hits and two earned runs. During the month, he had a 4.22 ERA in 13 innings. For the season, he is 0-1 with a 3.52 earned-run mark in 23 innings.
Though he was a closer in Japan with the Rakuten Golden Eagles, he is still being used in setup situations by the Padres or entering games with the team well ahead or behind.
Yu Darvish
Darvish, now 38 and starting the third season of a six-year, $108 million contract, halted his throwing program on March 17 because of what was referred to as “general fatigue”. Then it was announced on March 21 that he will miss the beginning of the season because of inflammation in his right elbow.
Darvish began throwing off a mound earlier in April, but the sessions were low intensity. He ramped up somewhat as the month went on and made a rehab start for AAA El Paso on May 14. However, he said a few days later that he felt tightness in his elbow and did not feel ready to pitch in a big league game. He played catch at Petco Park on May 26, after which Padres manager Mike Shildt said, “He’s making steps forward.”
Darvish also missed a lot of time in 2024 season because of injuries and a personal issue.
Masataka Yoshida
Signed to a five-year, $90 million contract before the 2023 season – which some thought was an overpayment – Yoshida has yet to play in 2025 because of injuries.
On October 3, he underwent labral repair on his right shoulder that was deemed successful. His labrum had started bothering him late in his rookie year of 2023, but he played through the discomfort all last season, when he was used exclusively as a DH. It was thought that he would be ready for the start of this season, and he batted .286 in 35 spring training at bats. However, his shoulder is still not recovered enough for him to throw well from the outfield, and the Red Sox have opted to keep him on the Injured List until he is fully ready.
On May 22, the Red Sox transferred Yoshida from the 10-day IL to the 60-day IL.
Also, Rafael Devers is now the regular designated hitter after Boston signed Alex Bregman to play third base, so, DH is no longer a likely landing spot for Yoshida, who is rated as sub-par defensively. So it’s an interesting conundrum – read more details here.
NOTES: By any standard, Kenta Maeda had a rough 2024, the first season of a two-year, $24 million deal with the Detroit Tigers, and after his 2025 campaign began poorly – a 7.88 ERA and a 1.875 WHIP in eight innings – he was designated for assignment on May 1. He later signed a minor-league deal with the Chicago Cubs and was assigned to AAA Iowa. Through May 28, he had made three starts for Iowa and lasted a total of just 6.2 innings, giving up 18 hits, seven walks, and 18 earned runs. His ERA – 24.30. His WHIP – 3.750. Female pitcher Ayami Sato was the first woman to play in a Canadian men’s professional baseball league on May 11. Playing for the Intercounty Baseball League’s Toronto Maple Leafs, Sato struck out one batter and allowed no baserunners in two innings against the Kitchener Panthers. Her next outing, a week later, was difficult, as she allowed seven hits and seven earned runs in two innings. By the end of May, she had made three appearances, with a 1-0 mark and 12.60 ERA . . . The 27-year-old pitcher Shinnosuke Ogasawara signed a two-year deal with Washington in the off-season, but he was optioned to AAA Rochester on March 21. [As of April 28], he had made three starts covering 15 innings and was 1-1 with a 4.80 ERA . . . The Athletics landed a compelling player during the international signing period in January, signing 18-year-old Japanese two-way (pitcher/infielder) prospect Shotaro Morii. He is now with the Athletics’ team in the Arizona Complex (Rookie) League and has a slash line of .233/.393/.256 after 14 games . . Slugging first baseman Rintaro Sasaki, Japan’s all-time high school home run leader, is averaging .269 with seven home runs, a .790 OPS, and 41 RBIs in 52 games. He has 47 strikeouts and 25 walks in 201 at bats . . . Another Japanese player who opted to play college ball in the U.S. is Itsuki Takemoto, who pitched in the Koshien tournament as a high-schooler with Chiben Wakayama High School and then went to the University of Hawaii. At the moment, he is 2-6 with a 5.75 ERA in 14 starts on the mound and is batting .256 with a .653 OPS . . . Relief pitcher Koyo Aoyagi signed a minor-league deal with the Philadelphia Phillies in the off-season and was a non-roster invitee to spring training. He was reassigned to minor-league camp on March 15 and has a 3.29 ERA and high 1.75 WHIP in 15 relief appearances (13.2 innings) for AAA Lehigh Valley . . . Another import signing a minor-league contract was Shintaro Fujinami, who took a minor-league deal with an invitation to spring training from the Seattle Mariners. His struggles with command have continued, as he has walked 21 batters and allowed nine hits in 14.2 innings. His WHIP is an unsightly 2.045 . . . Slugger Munetaka Murakami of the Yakult Swallows, who broke the record for home runs in a single season by a Japanese-born player with 56 in 2022, announced that this will be his last season in NPB and he will then look to move to MLB. However, he’s played just one game with the Swallows and only five with its developmental team because of an oblique strain. He was bothered by it in spring training and re-aggravated it in a game on April 18. There is currently no timetable for his return to action.
