Lance McCullers will miss all of 2023 due to his flexor tendon injury:

McCullers, who did not pitch in a game this season, originally injured the flexor tendon during the 2021 American League Division Series and aggravated the injury during a spring training bullpen session in February, according to the team.

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McCullers, 29, also missed most of last season because of the flexor tendon injury, going 4-2 with a 2.27 ERA in eight regular-season starts and 0-1 with a 5.87 ERA in three postseason starts.

ESPN.com

Astros suffered some major injuries this season but are still in the hunt for another division title.