Is Tomoyuki Sugano’s Early-Season Success Sustainable?

Through five starts, Sugano is 2-1 with a 3.54 ERA. Compared to the dumpster fire that has been the rest of the Orioles rotation, Sugano has been their knight in shining armor.

Sugano has pitched quite successfully thus far by using some unusual methods. Specifically, he has only logged nine strikeouts across his five starts (28 IP), good enough for a 2.9 K/9. A strikeout rate that low is unprecedented, but Sugano has certainly made it work to this point.

So, can Sugano sustain this success, or will MLB hitters eventually figure him out? Let’s dig a bit deeper to find out.

The Lack of Punchies

When analyzing Sugano’s stats, as was just mentioned, easily the thing that stands out the most is his low strikeout count.

In a strikeout-driven league, a 2.9 K/9 is shockingly low. To no surprise, that’s the lowest K/9 in Major League Baseball, and Sugano is the only starter with a mark below 3.00.

In NPB, Sugano was not a strikeout pitcher, though. Sugano’s highest K/9 mark was 9.3 back in 2016. Since 2020, Sugano averaged 7.06 strikeouts per nine, a mark that would still put him near the bottom of MLB this season.

That said, just because Sugano has not been effective at striking guys out does not mean that he is having command issues.

So far this season, Sugano has walked five hitters in 28 innings, good enough for a 1.6 BB/9. Amongst other qualified starters, that puts him 13th in baseball, sandwiched between the reigning AL Cy Young winner, Tarik Skubal, and an early 2025 Cy Young contender, Hunter Brown.

Sugano’s BB/9 is more alike to his NPB days compared to his strikeout numbers. Throughout his entire career in NPB, he averaged a 1.7 walks per nine.

Sugano might not be striking out the world, but he is doing a great job at limiting walks, suggesting that he is excelling at pounding the zone.

Real vs Expected Stats

With how rough the start of the season has been for the Orioles, fans and analysts have been using expected stats to tell if the team has been extremely unlucky, or if they really have been playing as poorly as their record indicates.

In Sugano’s case, his expected stats are very concerning. In a rotation that has been one of the worst in baseball, Sugano has the highest xERA, xBA, xSLG and xwOBA among Orioles starters.

Sugano’s ERA of 3.54 ranks second in Baltimore’s rotation only behind Zach Eflin, who has missed some time due to injury. However, Sugano’s xERA of 6.11 ranks highest on the entire team.

With an opponent batting average of .252, Sugano ranks eighth on the team and second amongst starters. His expected batting average is more discouraging, as his mark of .310 ranks last on the team.

The most concerning difference lies with Sugano’s slugging percentages. An actual slugging percentage of .449 is not great. Compare that to his expected slugging percentage of .572, and it certainly raises some red flags.

For reference, a slugging percentage of .572 (Sugano’s expected slugging percentage) would be in the top 15 among MLB hitters. You can confidently see that Sugano may be playing with fire.

Now, the expected stats must be taken with a grain of salt. They are expected for a reason. If Sugano continues to pitch like this for the rest of the season, Orioles fans are not going to care that his xSLG is close to .600.

However, expected stats can indicate that Sugano has been a little lucky so far, and it’s something to keep an eye on as the season progresses.

Pitching to Contact

So far, as touched on earlier, hitters are making a lot of contact against Sugano. That abundance of contact has led to Sugano’s expected stats being the worst of any Orioles pitcher.

However, Sugano has one of the best BABIP marks in the league at .228. He’s managing that despite allowing a hard-hit ball 39.8% of the time. He’s also sporting a medium-hit rate of 50%, which is within the bottom third of the league amongst qualified starters.

Still, the contact being made against Sugano to this point has been manageable, forcing the defense to work behind him.

Additionally, Sugano has done an incredible job at tightening up when opposing hitters reach base. Despite a WHIP of 1.14, Sugano strands 89.4% of baserunners, which is the fourth-highest percentage in the league.

While hitters may be reaching base, Sugano has done a good job of limiting the damage. That certainly helps explain some of his early-season success to this point.

What Can We Expect Moving Forward? 

So far, especially in the context of the rest of Baltimore’s rotation, Orioles fans can be pretty happy with Sugano’s performances. There were always going to be some growing pains as Sugano transitioned leagues, and he’s handled the challenge quite well to this point.

However, MLB is the premier professional baseball league in the world for a reason. At some point, hitting coaches and batters are going to find a way to attack Sugano. Likewise, his stats do indicate that he may be receiving some beneficial luck so far.

As Sugano settles in, the strikeout and swing-and-miss numbers must increase if he wishes to see true season-long success. With his arsenal, Sugano does not need to pitch like Paul Skenes to dominate. However, a 2.89 K/9 simply will not cut it in this league.

As the Orioles’ rotation hopefully gets healthier, it will be very interesting to see how Sugano fits into the plans when other arms return.