For the fifth time this season, a lead was blown in the final minute of a Vikings game. Only this time — unlike Week 2 at Chicago or the ensuing pratfalls against Cleveland, Dallas and Green Bay — it was a Vikings quarterback making key plays under pressure against a reeling Bears defense that couldn’t make a stop on the road.

Vikings backup Matt Cassel, who relieved injured Christian Ponder (concussion) in the final minute of the first half, completed six of 10 passes to four different receivers for 82 yards and four first downs en route to a game-tying 30-yard field goal by Blair Walsh with 20 seconds left. That, coupled with an earlier touchdown drive, enabled Cassel to erase a 20-10 fourth-quarter deficit in a game the Vikings won 23-20 in overtime.

“Matt did a good job in relief,” coach Leslie Frazier said. “We’ll monitor Christian’s health throughout the week and we’ll sit down and talk as a staff to see what’s the best direction to go.”

With 2 minutes, 40 seconds left in regulation, the Vikings were going backward. They took possession at their 9-yard line and promptly lost 3 yards when Cassel dropped the shotgun snap from center. Two more plays netted just 2 more yards, leaving the Vikings facing fourth-and-11 at their 8-yard line with 1:55 left in regulation.

“It was crunch time there,” Cassel said.

Ya think?

That’s when Jerome Simpson entered the picture with what he says is his favorite route to run.

“A dig route,” he said. “It’s my favorite to run just because I can run across the corner’s face or the safety’s face over the middle. You keep running and it’s hard for them to defend. That’s one of my best routes. My coaches tell me I’m one of the best guys in the league at that route.”

On that particular play, Simpson made a 20-yard grab in front of free safety Chris Conte.

“The offensive line did a heck of a job holding up there,” Cassel said of a unit that allowed five sacks on the day. “We had a backside in-cut against split-safety coverage and that’s where the read took me.”

And without that play?

“Game over,” Simpson said.

Cassel completed 61 percent of his passes (20 of 33) for 243 yards, threw an 8-yard fourth-quarter touchdown to Greg Jennings and gave up an interception that would have been a 4-yard touchdown pass late in the fourth quarter had tight end Rhett Ellison not let the ball bounce off his chest at the goal line.

Cassel, who went 1-1 as a starter earlier this season, also threw Ponder’s future back into doubt. Cassel not only had the game-tying drive, he also completed six of nine passes to four different receivers for 53 yards and the touchdown to Jennings to draw the Vikings within three points earlier in the fourth quarter.

Ponder had started six consecutive games but was ineffective when he left with a 7-6 lead. In Ponder’s six possessions, the Vikings punted five times while he went 3-for-8 for 40 yards and a 54.2 passer rating.

Cassel, as usual, wasn’t willing to wade into any controversy when asked if he should start next week.

“You know what, I don’t make those decisions,” he said. “I might not always agree with it, but at the same time, my job is to go out there and be prepared and be accountable to those guys in that locker room.”