Devenski, a right-hander, pitched in 61 games for the Astros this season, posting a 4.83 ERA and 72 strikeouts in 69 innings.
This is the first time Devenski is activated this postseason.
Abreu, also right-handed, pitched just once in the ALCS against the Yankees, where he gave up a home run and walked two batters.
First pitch is at 7:08 p.m. at Minute Maid Park.
Gerrit Cole will start for the Astros. Max Scherzer will start for the Nationals.