The Dallas Cowboys are fearing the worst with wide receiver Michael Gallup sustaining a suspected torn ACL in his left knee in Sunday's 25-22 loss to the Arizona Cardinals.

Gallup landed awkwardly when he caught a touchdown in the second quarter of the defeat, before limping off the field and leaving for the locker room on crutches.

Cowboys owner and general manager Jerry Jones confirmed Gallup will undergo an MRI on Monday to confirm the severity of the injury but teammate Dak Prescott and head coach Mike McCarthy feared the worst.

"It was tough, very tough," Prescott said at the post-game news conference. "Coming in at half-time and going to see him, just unfortunate. A guy that I love. Can't get a better teammate than MG. Sick about it."

McCarthy added: "Feel terrible for Michael. Obviously made a huge play, but you could see just the way he came down."

Gallup has had 35 receptions for 445 yards and two touchdowns this season for the playoff-bound Cowboys.