DETROIT - Perhaps Jamarca Sanford is no longer the Megatron of liability everyone thought he was when he lost his starting strong safety job to Mistral Raymond during training camp.

In his first start since last season, Sanford rebounded from an awful beginning to play a significant role in the Vikings' 20-13 upset of the Lions at Ford Field on Sunday. From his three passes defensed, to forcing his second fumble in two weeks, to recovering that fumble, to his five solo tackles, to his role in Lions receiver Calvin Johnson catching only five of the 12 balls thrown his way, Sanford exceeded all expectations. He also teamed with rookie Harrison Smith -- who also had three passes defensed -- to give the Vikings some of the best safety play they've had in years.

"A lot of guys lose their starting jobs from one year to the next," said left guard Charlie Johnson. "But it's the rare player who doesn't go in the tank. I think Jamarca Sanford is an example of what this team is all about."

Sanford's day began with a 56-yard pass interference penalty against Johnson. But, as he would point out later, it didn't cost seven points. The Lions were held to a 40-yard field goal.

"We'll take pass interference over an 80-yard touchdown pass on the first play any day," said Sanford, proving teammates right that he does indeed consider life's glass half-full.

It wouldn't be the last time the Lions would throw deep or try to test Sanford and the Cover-2 scheme the Vikings relied on heavily throughout the game. But Sanford responded with the physical style that's his strength.

He delivered a hard shot to tight end Brandon Pettigrew, breaking up a pass inside the 10-yard late in the first half. Three plays later, he and Smith sandwiched Johnson in the end zone on second-and-goal as Smith blasted the ball out of Johnson's grip. One play later, Pettigrew was closely covered when he dropped a pass in the end zone.

"You just got to keep hitting a guy over and over and over, and they're going to get those alligator arms," Sanford said. "I couldn't imagine being a receiver and coming across the middle and getting hit as hard as we were hitting Calvin and those guys. Calvin took a beating today."

Sanford also came up from his two-deep spot to blast running back Mikel Leshoure after a 14-yard gain late in the third quarter. Leshoure fumbled and Sanford recovered.

"You lick your chops because it's the open field so you think to yourself, 'It's me and him,'" Sanford said. "You got to make the play. You just got to take your shot and try to blow him up."

Earlier in the quarter, Sanford also stuffed Leshoure for no gain on third-and-1, forcing the Lions to punt from the Vikings' 40-yard line.

"After the game, I went up and gave Jamarca a hug," said Vikings receiver Percy Harvin, who has been a source of encouragement for Sanford since he lost his starting job. "I saw he was a little down after losing his starting job, so I talked to him and told him his chance would come. And when it did, he was ready for it."

Sanford isn't sure what will happen when Raymond returns in two to four weeks. But he figures he'll be able to handle whatever it is.

"This game of football tests you mentally as well as physically," Sanford said. "You just keep working because things don't always go as they're planned."