Schaub injured his left shoulder on the Texans' first play Sunday. After being sacked by Jaguars defensive end Derrick Harvey, Schaub stayed on the ground as trainers rushed onto the field. Schaub eventually walked off without any help, but he spent just a few minutes on the bench before heading to the locker room for tests.
"He had a dislocation, and they were able to get it back and in, and he wanted to come back out to play," Kubiak said. "So it was a gutsy performance on his behalf, (but) we came up a little bit short."
Rex Grossman replaced Schaub and threw an interception on his second pass attempt. Schaub returned and finishing 19-of-27 passing for 207 yards and one touchdown with one interception.
Schaub's injury came on a day when the Texans already were playing without running back Steve Slaton, who sat out with a shoulder injury.
The Associated Press contributed to this report.