Ready or not, the Teddy Bridgewater era is underway with the Minnesota Vikings.

The rookie quarterback from the University of Louisville was thrust under center in the second quarter of Sunday’s 20-9 loss to the New Orleans Saints at the Mercedes-Benz Superdome when veteran starter Matt Cassel had to leave the game after fracturing several bones in his left foot.

Cassel, who did not speak with reporters afterward, exited the stadium on a golf cart with crutches at his side sporting a boot on his injured foot. Vikings coach Mike Zimmer declined to speculate on how long Cassel will be sidelined but said Bridgewater will start next Sunday against the Atlanta Falcons at TCF Bank Stadium in Minneapolis.

Bridgewater, who completed 12 of 20 passes for 150 yards with no touchdowns and no interceptions, inherited a 13-3 deficit with with 12:15 remaining in the first half and promptly led the Vikings to the first of two field goals under his direction.

“I wasn’t nervous because this is where I always wanted to be,’’ said Bridgewater, the 32nd overall selection and last pick in the first round of the NFL draft. “Unfortunately, the way it happened wasn’t the way that I expected it to be. But I was able to relax and guys put their trust in me.

“Coach (Vikings offensive coordinator Norv) Turner told me, ‘Hey, this is your time, take advantage of it. Relax, have fun and go play.’ ”

Bridgewater also rushed six times — one by design in the red zone for 9 yards — for 27 yards and finished with a 83.3 passer rating. Outside linebacker Junior Galette acknowledged that Bridgewater presented the Saints defense with “a lot of problems’’ because of his ability to extend plays.

Bridgewater last played in the Superdome as a college sophomore, winning MVP honors after leading Louisville to a 33-23 upset of heavily-favored Florida in the 2013 Sugar Bowl.

“I thought (Bridgewater) did some good things today,’’ Zimmer said. “Obviously, it’s a tough situation going in there like he did. He made some very good throws. Obviously, he missed a couple. I thought he was very composed. I didn’t see any panic. There were some issues with the headsets, but he handled it well.

“He’ll be ready (next week). It’ll help that we go back home and it’ll help him to get all the reps. I think that will be good for him.’’

In a span of 10 days, the Vikings have lost the services of two important pieces to their offense — Cassel and perennial All-Pro running back Adrian Peterson, who has been placed on the exempt/commissioner’s permission list while he deals with a child abuse case in his home state of Texas.

Now, Bridgewater will be asked to shoulder the load for an offense that has been limited to 217 yards and 247 yards in back-to-back losses against New England (30-7) and New Orleans (20-9).

“We can’t worry about what we don’t have,’’ Zimmer said. “What we have to do is worry about what we do have and how we can go forward from where we are. No one is going to feel sorry for us. No one is going to cry that we don’t have this guy or that guy, and we’re certainly not going to make excuses about it.

“There’s no magic wand. We just got to keep going. I felt like a week ago we didn’t withstand what New England gave us. Our whole thing was if we get punched in the mouth this week (against New Orleans), we would punch back. And, I think we did that. The one thing I feel good about this football team is they got a lot of heart. Now we’ve got to play better.’’