DL Brace undergoing MRI on ankle

FOXBOROUGH, Mass. -- Second-year defensive lineman Ron Brace, who left Thursday's preseason game against the Rams in the fourth quarter with an ankle injury, is undergoing an MRI to determine the severity of the injury, according to his representatives.

Brace played in a reserve role at left defensive end and finished the game with seven tackles, one sack and also drew a holding penalty in the second quarter on a running play.

The Patriots are thin at defensive end after placing starter Ty Warren on season-ending injured reserve (hip).

Brace, a 2009 second-round draft choice who opened training camp on the non-football injury list before returning to practice Aug. 15, projected as the top backup at that spot behind Gerard Warren. He entered Thursday's game on the third series.