An MRI on Mark Sanchez's injured right shoulder indicates a partially torn labrum, according to ESPN's Chris Mortensen.
A source said Sanchez will seek a second opinion on his shoulder this week from surgeon Dr. James Andrews.
A confirmed partial tear of his labrum -- suffered last month in a Jets preseason game -- may not require surgery.
Jets coach Rex Ryan declined to address reports of the injury after the game.
"He remains day-to-day for us, and that's what he'll continue to be," Ryan said.
According to ESPN:
Sanchez, who did not address the media after the game, was seen throwing with his left hand during pregame warm-ups Sunday. He is expected to miss at least a few weeks with the shoulder injury and could be placed on injured reserve, sources told ESPN.com.
The Jets reportedly re-signed quarterback Brady Quinn on Monday morning.
Jets general manager John Idzik described Sanchez's return as "unpredictable" and has downplayed the possibility of the quarterback being placed on season-ending IR. Jets owner Woody Johnson disputed speculation that Sanchez could be released this season, saying he "will be on the team."