McCullers was great in a Game 1 win against the Chicago White Sox in the division series, pitching scoreless ball into the seventh. But the right-hander left Game 4 after four innings because of forearm tightness.He is listed as being part of Houston's taxi squad for the ALCS.
Manager Dusty Baker said Friday that McCullers has an injured muscle in his forearm and is "not able to throw a ball right now," but tests revealed no structural damage. His status remains unclear for the World Series should the Astros advance that far.
"That's good news," Baker said. "That's great news. I hope he heals soon. We don't know if he is going to be available for the World Series or not, so we just have to see."
Replacing him on the roster is right-hander Jake Odorizzi, who was left off the division series roster after a disappointing first season in Houston. The only other change to Houston's roster from the ALDS is the addition of left-handed reliever Blake Taylor in place of catcher Garrett Stubbs, who will be on the taxi squad.
Game 1 was won by the Astros 5-4.
The Red Sox retained the same roster from the ALDS except for replacing pitchers Matt Barnes and Austin Davis with left-hander Darwinzon Hernandez and right-hander Hirokazu Sawamura.
Both teams will have 13 pitchers, two catchers and 11 other position players for this series.
The Associated Press contributed to this report.
Homers from Altuve, Correa lift Astros to Game 1 win
Jose Altuve and Carlos Correa both homer into the Crawford Boxes as part of the Astros' victory over the Red Sox in Game 1 of the ALCS.