Las Vegas quarterback Aidan O'Connell was carted off the field in the third quarter of Sunday's 28-13 loss to the Tampa Bay Buccaneers after suffering a knee injury.
The Raiders quickly ruled out O'Connell, who also left the field with an air cast to support his injured knee. O'Connell went down after he was hit following a scrambling completion to Jakobi Meyers. O'Connell was replaced under center by Desmond Ridder.
"It doesn't look good," coach Antonio Pierce said after the game of O'Connell's knee injury.
O'Connell left the game 11-of-19 passing for 104 yards and an interception. Ridder was 12 of 18 for 101 yards and led a field goal drive in relief.
This marks the latest injury for a Raiders quarterback in what has been a trying season for Los Angeles.
O'Connell previously missed time after he fractured his thumb in Week 7 and just returned to the starting lineup for the Raiders' Black Friday loss to the Chiefs.
Week 1 starter Gardner Minshew is out for the season after suffering a fractured collarbone last month.