Dallas Cowboys LB Jabril Cox hobbled out of U.S. Bank Stadium in Minneapolis on crutches following Sunday night’s electric win against the Vikings, according to Michael Gehlken.

The rookie linebacker was carted from the sideline to the locker room after suffering a right knee sprain during a Minnesota punt. He has an MRI scheduled for Monday in Dallas.

Cox has primarily been used as a special teams piece for the NFC East-leading Cowboys, but has seen an increase in defensive snaps since the team’s release of former starter Jaylon Smith.

The fourth-round pick from LSU had fans excited to see more of him after a big hit on New York Giants quarterback Daniel Jones in week 5.

If Cox is out for an extended period of time, the Cowboys defense may not be in big trouble. They may be thin-stretched, however, as the linebacking unit will have one less man to substitute in, and Cox’s promising rookie season may be upended for a couple weeks.