NEW ORLEANS -- New Orleans Saints quarterback Jameis Winston was carted back to the locker room with a knee injury during the second quarter of Sunday's 36-27 win against his former team, the Tampa Bay Buccaneers.

Coach Sean Payton said after the game that he thinks it's a "significant" injury.

Winston was injured during a horse-collar tackle by Buccaneers linebacker Devin White -- who was flagged 15 yards for pulling Winston down by the shoulder area of his jersey, forcing Winston to land awkwardly. Winston's left leg got pinned behind him as he hit the turf.

Trainers and medical staff looked at him on the field before helping him limp slowly to the sideline and into the medical tent. He was later assisted onto a cart and driven back to the locker room. Several teammates hugged Winston on his way off the field, including injured receiver Michael Thomas, who was watching the game on the sideline in street clothes.

Winston was replaced by veteran backup Trevor Siemian -- the only other QB available for the Saints. Backup Taysom Hill has been sidelined with a concussion since Week 5, and rookie Ian Book was a healthy inactive. Siemian finished with 159 yards and touchdown.

Winston completed 6 of 10 passes for 56 yards and a touchdown and scrambled four times for 40 yards before leaving the game with the score tied 7-7.