Texans quarterback Matt Schaub suffered an apparent right ankle injury in the third quarter of Sunday's 38-13 loss to the Rams, after a sack by another former 'Hoo, Rams defensive end Chris Long.
The team said after the game that Schaub was undergoing further tests, and they expected to know more Monday.
Before his injury, Schaub didn't have a turnover after throwing six interceptions, three of them returned for touchdowns in the past three games.
Texans backup quarterback T.J. Yates threw a pick-six after entering the game to replace Schaub, with Alec Ogeltree returning the interception 98 yards for a touchdown.
The Texans are now 2-4, and have lost four games in a row.