After Ponder left the game, Matt Cassel led a 10-point comeback in the fourth quarter and eventually directed the Vikings to a 23-20 overtime win. Cassel threw for 243 yards in relief of Ponder.
Ponder took a helmet-to-helmet hit on a two-yard completion to Greg Jennings near the end of the first half, and went to the locker room without his helmet to be evaluated.
"It's unfortunate that Christian got injured," coach Leslie Frazier said. "It's great that Matt came in and did the things he did. We'll sit down on Monday and talk about where we are and figure out where Christian is, health-wise, over the course of the week."
Asked if Ponder would be in consideration to start if he is healthy, Frazier said, "Of course. He'd have to be in consideration, for sure."
Before he got hurt, Ponder was just 3-of-8 for 40 yards, having been sacked three times. He had started the Vikings' last five games after initially losing his job to Cassel, and later Josh Freeman, because of a rib injury in September. He was coming off his best game of the season in last Sunday's tie against the Green Bay Packers, in which he completed 21 of his 30 passes for 233 yards and a touchdown.
Information from The Associated Press was used in this report.