Astros get good news on Tatsuya Imai, but that raises more questions than it answers

Eric Cole

Mar 29, 2026; Houston, Texas, USA; Houston Astros starting pitcher Tatsuya Imai (45) walks to the dugout before the game against the Los Angeles Angels at Daikin Park. Mandatory Credit: Troy Taormina-Imagn Images / Troy Taormina-Imagn Images

Tatsuya Imai was supposed to be the crown jewel of the Houston Astros' offseason. Imai was widely considered to be one of the better starting pitchers available, and it was frankly surprising to see the Astros end up with him, given their lack of experience in the Japanese player market. Unfortunately, Imai has not yet lived up to that expectation as a rotation anchor, and there are now real questions as to when he will pitch again.

Some sort of adjustment period for Imai was inevitable. The MLB mounds and weather are different than those in Japan, the playing schedule is different, and MLB hitters are much better on average than those in the NPB. However, Imai's "arm fatigue," which put him on the IL, hinted at a deeper issue.

The good news is that Imai did have scans done on his arm, and they came back clean. While that does likely mean there isn't a serious injury issue here in all likelihood, it also doesn't really explain what is going on with Imai or when he could return.

Tatsuya Imai's medical tests went well, but answers for the Astros remain elusive

One can take some heart from the fact that Imai is already playing catch, so there does seem to be some truth to the Astros' position that they think building up his arm strength while helping with the culture shock of moving over to the US, and MLB will help.

However, what neither Imai nor the Astros can do is predict when he could return to Houston's rotation. If Imai had a diagnosis like elbow tendonitis, a shoulder strain, or whatever, there is existing information out there about how those injuries are treated and how long players are typically on the shelf with them. There is no textbook for "arm fatigue and moving countries/leagues," and both the Astros and Imai will just have to wing it.

One hopes that this is a temporary concern, and Imai comes back better for this. Unfortunately, there will be questions and concerns about him and his signing until Imai comes back and shows he can contribute in the majors. For the moment, that is anything but certain to actually happen.

Eric Cole

I started my career writing about baseball covering the Atlanta Braves for SB Nation's Talking Chop back in 2015 which has since been renamed Battery Power. After years of writing for those fine folks, I made the decision to take over as Site Expert at House That Hank Built before becoming a full-time MLB Staff Writer for FanSided in 2023. Along the way, I have been a guest on multiple ESPN radio affiliates as well as 680 The Fan and 92.9 The Game to discuss Braves baseball and especially Braves prospects and was a long-time host on the Battery Power podcast. These days, I continue to write about the Braves as well as covering the Astros, Padres, and Angels with particular expertise with minor league coverage, the MLB Draft, and bashing Anthony Rendon when possible. When I am not writing about or talking about baseball (which is seldom), I am an avid baseball card collector (Maddux and Soroka being my primary personal collections) and I also collect shark teeth. All other sports are mostly dead to me as my Bills have broken my heart too many times.