Foster didn't play in the first quarter and was on the bench for the first drive of the second quarter. He entered the game with just under seven minutes remaining in the second quarter.
Backups Steve Slaton and Derrick Ward got off to a good start. Ward scored on a 33-yard touchdown run on Houston's opening drive, and Slaton had 47 yards from scrimmage in the first quarter.
Foster leads the NFL with 406 rushing yards through four games.
Houston played without leading wide receiver Andre Johnson, who was inactive with a sprained right ankle.
Copyright 2010 by The Associated Press