September 23, 2025
Analysis
The Astros announced that Walter was slated for elbow surgery a couple of weeks ago, but now that we know he specifically underwent a Tommy John procedure, it's safe to assume the left-hander won't return to a big-league mound until 2027. It's a notable loss for the Astros' rotation, as Walter finished his first season in Houston with a 3.35 ERA and 0.93 WHIP over 53.2 innings spanning nine starts.