Fans aren’t the only ones wondering what might have been had Matt Cassel been the Vikings’ starting quarterback all season.

“Yeah, you wonder,” receiver Greg Jennings admitted Sunday after catching a career-high 11 passes for 163 yards, including a 57-yard touchdown, in a 48-30 upset of the Eagles at Mall of America Field.

Jennings mentioned that to Cassel before he went out and completed 26 of 35 passes (74.3 percent) for 382 yards, two touchdowns, an interception and a 116.6 passer rating while improving to 2-2 as a starter this season.

“He’s like, ‘We got three games. Let’s make the best of it,’ ” Jennings said. “I love that.”

So does embattled Vikings coach Leslie Frazier, who had to declare five starters, including Adrian Peterson, and backup running back Toby Gerhart, because of injuries. With the running game averaging only 2.4 yards on 35 carries, it was Cassel’s fourth-highest passing yardage total ever that carried the Vikings to their highest point total since a 50-10 victory over Jacksonville on Dec. 20, 1998.

“It seems like his experience really shows up,” Frazier said. “The things he is seeing [during games] really helps [offensive coordinator] Bill [Musgrave] and our offensive staff to call plays. Veteran experience is probably what separates him.”

Yet the Vikings at one point had Cassel as their No. 3 quarterback. After starting the Vikings’ fourth and fifth games, Cassel was a backup for seven games until Christian Ponder’s concussion gave him another chance at Baltimore on Dec. 8.

“We made those decisions at the time for different reasons,” Frazier said. “We always felt good about Matt, but there were some things we needed to see. Unfortunately, we weren’t able to get wins when we were going through the process. That would have been a lot better. [I] knew why we were doing it back then, so hindsight is always 20/20.”

Cassel targeted the wide receivers 28 times, completing 21 of them for 312 yards and two touchdowns. He had six completions of 22 yards or more to three different targets. Rookie Cordarrelle Patterson also drew a 30-yard pass interference penalty.

Cassel refuses to entertain “what-if” questions and speculate on whether he’ll return next season or exercise his option to leave. Obviously, his early-season patience is paying off.

“You don’t really have much of a choice,” Cassel said when asked how he’s remained so patient. “I think the main choice is whether you’re going to let that get to you or you’re going to continue to move forward and have a positive attitude and help the guys around you. I chose to go that route than the other.”

Jennings definitely wants a second act with Cassel in 2014. Asked if he’ll lobby for Cassel to return, Jennings smiled like a guy whose four best games and all four touchdowns this season have come with Cassel at quarterback.

“Absolutely,” Jennings said. “I love Matt. I do. I think he brings a lot to the table.”