Kirk Cousins, the Washington Redskins’ fill-in starter at quarterback, left Monday night’s preseason game against the Pittsburgh Steelers after injuring his right foot.

The extent of the injury was not immediately clear. The Redskins announced that Cousins was questionable to return to the game. But Cousins left the field soon thereafter, apparently on his way to the Redskins’ locker room. The team late in the second quarter announced Cousins as out with a foot sprain.

Cousins grabbed his right foot after being tackled by Steelers linebacker Lawrence Timmons on the sideline at the end of a second-quarter run. He made his way back toward the middle of the field but sat on the ground and again held his foot as he was examined by members of the Redskins’ medical staff. Cousins walked off the field to the sideline and was replaced by third-string quarterback Rex Grossman.

The second-year pro was making his second start of the preseason in place of starter Robert Griffin III. The Redskins plan to withhold Griffin from the entire four-game preseason as he works his way back from knee surgery in January.

Cousins made one start last season as a rookie and won a key game for the Redskins in Cleveland. He would be in line to start this season’s opener against the Philadelphia Eagles if Griffin does not return to the lineup that night.

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