FRISCO, Texas — When the Dallas Cowboys play the Pittsburgh Steelers on Oct. 6, they could be without their top two defensive linemen.

An MRI on Friday confirmed edge rusher Micah Parsons suffered a high left ankle sprain in the fourth quarter of the Cowboys’ 20-15 win against the New York Giants on Thursday, while defensive end DeMarcus Lawrence suffered a right midfoot sprain that will keep him out for multiple weeks, according to sources.

It’s a major blow to a defense that struggled against the run in losses to the New Orleans Saints and Baltimore Ravens but gave up just 26 yards on 24 carried against the Giants.

Parsons and Lawrence are the Cowboys’ top two pass rushers. Lawrence leads the Cowboys with three sacks this season and Parsons has recorded at least 13 sacks in each of his first three seasons.

Parsons was injured rushing the passer from the middle of the Giants’ line. He was engaged with center John Michael Schmitz Jr. when guard Greg Van Roten fell on the back of Parsons’ leg. Parsons was tended to by medical staff before limping to the sideline. Eventually, he was taken off by a cart to get X rays.

After the game, he took a golf cart to the team bus.

Parsons has missed just one game in his career (2021, COVID). Lawrence had played in 38 straight games.

Lawrence suffered his injury in the third quarter while chasing Daniel Jones, stopping quickly after the quarterback changed directions. He limped off the field and went to the locker room. While he returned to the sidelines, he did not return to the game. After the game he said the injury was not related to the foot fractures he had earlier in his career.

Without Parsons and Lawrence, the Cowboys ended Thursday’s game with rookie Marshawn Kneeland and Chauncey Golston playing defensive end. In the past two weeks they have elevated veteran Carl Lawson from the practice squad. Tyrus Wheat is on the 53-man roster but has been inactive the past two games.

Losing two key defenders is hardly the best way to go into a difficult stretch of the season. After the Steelers, the Cowboys play critical NFC games against the Detroit Lions (Oct. 13) and San Francisco 49ers (Oct. 27) with the bye week coming in between.