With 23 seconds left on the clock and an estimated 66,807 fans on their feet at U.S. Bank Stadium, it seemed as though the Vikings' little slump had ceased.

Pat Shurmur's offense had finally broken through for a go-ahead touchdown. The defense had allowed the Detroit Lions to earn only two first downs in five second-half drives. And Blair Walsh's services were no longer needed.

But a three-man rush led to a 27-yard gain, followed by a 58-yard field goal from Lions kicker Matt Prater, who crushed it through the uprights as time expired to send the game into overtime and Vikings fans slumping into their purple seats.

They would soon head to the exits after Lions wide receiver Golden Tate shook free from cornerback Xavier Rhodes and safety Harrison Smith on the sideline, then catapulted over the goal line for the walk-off winner. The 22-16 loss was the Vikings' third straight.

At 5-3, the Vikings are still in first place in the NFC North. But the stunning loss to the Lions left them wondering when their freefall might come to an end.

"I don't know. We're kind of shocked right now," Vikings cornerback Captain Munnerlyn said. "We're definitely fixing to see what this team is made of now."

After Detroit scored a touchdown with five seconds left in the first half to take a 10-3 lead, the Vikings spent most of the second half trying to catch up.

They pulled within a point in the third quarter when quarterback Sam Bradford, with nose tackle Linval Joseph lined up at fullback, found tight end Kyle Rudolph in the end zone for a touchdown. But Walsh missed the extra point.

The Vikings twice converted on third down to advance into Lions territory again. But Walsh's go-ahead attempt from 46 yards out was blocked by Lions defensive tackle Tyrunn Walker, who leaped high to swat down the kick.

"We've got to obviously make some kicks," said coach Mike Zimmer, who after the game did not want to evaluate where things stand with his struggling kicker.

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The defense held the Lions to their fourth consecutive three-and-out in the second half. But Prater was good from 53 yards, increasing the Lions' lead to 13-9.

The Vikings, still down four points midway through the fourth quarter, moved inside the 20-yard line for the fourth time. They needed 2 yards for a first down and had two plays to get it. But Matt Asiata was stuffed on fourth-and-1 after fellow running back Jerick McKinnon gained 1 yard on third down.

"We take pride in getting those [short-yardage runs] and scoring in the red zone," left tackle Jake Long said. "But we did not get those today."

On their first four trips inside the 20, the Vikings, 28th in red-zone touchdown percentage entering the game, scored only nine points and punted once. But down to their last opportunity at the end of regulation, they found pay dirt.

After Cordarrelle Patterson dropped a would-be touchdown in the end zone in the final minute and fellow wide receiver Stefon Diggs kept hope alive with a fourth-down grab, the Vikings faced third down at the Lions 1.

Shurmur, in his first game as interim offensive coordinator after Norv Turner's resignation, called for a handoff to blocking tight end Rhett Ellison, who lined up on the left end then ran to his right behind the line of scrimmage to take the handoff before plowing into the end zone to put the Vikings up 16-13.

"They didn't see it coming, so it worked out," Ellison said of his first NFL carry.

But Zimmer's questionable clock management at the end of that drive left enough time for Lions quarterback Matthew Stafford to complete a 27-yard pass to wide receiver Andre Roberts. The prevent defense that the aggressive head coach uncharacteristically called gave Stafford enough time to locate Roberts.

Prater then tied it up with the longest kick in U.S. Bank Stadium's brief history.

On the first and only drive in overtime, a pass interference penalty on Rhodes bailed out the Lions. Three plays later, they scored the game-winner on another third-and-long play when Tate wiggled free from Rhodes and Smith.

Even after the collapse, Zimmer said it was a step in the right direction. After all, the Vikings got dominated in double-digit losses in Philadelphia and Chicago.

"For the first time in three weeks this team fought like how I expect them to fight," Zimmer said after the Vikings' first loss at their loud, new stadium. "If we continue to do these kinds of things, then we'll win football games."

The wait continues, though, as their slump gets bigger and bigger by the week.

Matt Vensel covers the Vikings for the Star Tribune. matt.vensel@startribune.com