Minnesota Vikings quarterback Matt Cassel is adamant that teammate Teddy Bridgewater will be his backup as long as he is at the club.

Cassel was named as the club's starter for the 2014 season ahead of the Vikings' first-round pick in the 2014 Draft, and the 32-year-old has revealed that he won't be giving the job up anytime soon.

"I think I've had a tremendous off-season, I've worked as hard as I've ever worked. And I'm not going to look over my shoulder. You can't play that way," Cassel told reporters.

"You can't worry about, 'If I make a mistake what's going to happen next?' I think Teddy does have a tremendous future but hopefully as long as I'm here he's not playing."

The Vikings face the St Louis Rams in their season opener on Sunday.