Tatsuya Imai’s Startling Rehab Start Causes Concern for Astros Rotation

The Houston Astros need the NPB ace back quickly but his first rehab start showed he may need more time.

Joe Nicholson-Imagn Images

Tatsuya Imai's first rehab start with Double-A Corpus Christi on Tuesday night went well physically, but the results weren't what the Astros were looking for.

The NPB superstar allowed five runs on six hits and walked three over two innings of work. He threw just 31 of his 59 pitches for strikes and struck out two batters.

Imai hit the injured list after a disastrous start on April 10, where he walked four and only recorded one out. The initial report indicated that Imai experienced arm fatigue; however, the subsequent reports delved deeper.

Chandler Rome from The Athletic (subscription required) exposed that Imai has struggled to adjust to the American lifestyle so far. Imai indicated that his arm fatigue and struggle stemmed from this lack of adjustment.

Whether it's a lack of adjusting to America or not, his three starts have all gone in different directions this year. He began his MLB career by allowing four runs and walking four over 2.2 innings against the Los Angeles Angels.

Next time through the rotation, he threw a gem. He allowed just those hits and struck out nine over 5.2 scoreless innings, and recorded his first and only decision to this point, a win. His lackluster performance against the Seattle Mariners followed, and it's been downhill ever since.

The reports about his lack of acclimation have been all over the place, and he's struggled to begin his rehab outings. One constant this entire season has been a lack of precision around the strike zone and a plethora of walks. He walked 11 batters over his three starts earlier this year, and walked three more through two innings in his lone rehab outing.

Tatsuya Imai’s Return to the Rotation Is a Sight for Sore Eyes

Joe Nicholson-Imagn Images

If Imai can't pull it together after another couple of rehab outings, things will only worsen for the Astros rotation.

Hunter Brown and Christian Javier are both on the injured list for at least the next month with Grade 2 shoulder strains, and the pitching staff has severely struggled without them. Houston owns MLB's worst ERA by a long shot entering Wednesday night. The team's 5.96 ERA is a whole run higher than the third-highest contender, the Phillies.

Ironically, the ERA is lowered slightly to 5.66 with just the rotation, as the bullpen has been worse. Moving forward, Imai's return to the rotation is an exciting thing, despite there not being a clear timeline.

As of now, Mike Burrows, Lance McCullers Jr, Peter Lambert, Spencer Arrighetti, and Ryan Weiss are holding down the fort. Arrighetti has been the ace of the remaining staff with his 2.00 ERA over his first three starts.