The Rams were so confident in the power of rookie running back Todd Gurley that they tried a two-point conversion while trailing by four points in the first quarter of Sunday's game at TCF Bank Stadium.

It wouldn't be the last time they would underestimate the even higher power of Vikings nose tackle Linval Joseph.

Gurley got the ball, tried to cut and was slammed by 329 pounds of humanity wedged into a No. 98 jersey. The Rams trailed 10-6, which, ultimately, is why Greg Zuerlein's 53-yard field goal with 17 seconds left tied the score rather than won it.

"What did I see on the play?" Joseph asked after the Vikings' 21-18 overtime victory. "See ball. Get ball."

Joseph saw the ball and got the ball a lot Sunday. His 10 tackles (seven solo) tied the team high and Joseph's career best set in 2013 while with the Giants.

"Linval continues to be a terrific player for us," said coach Mike Zimmer, whose defense held the Rams to only three points after halftime. "He's tough, physical, smart, a great competitor, loves the game, loves his teammates, wants to do the dirty work. He's a guy I'm awful glad that we have."

The two biggest series of the game defensively for the Vikings came after Teddy Bridgewater's third-quarter interception and the first possession of overtime when Zimmer won the coin toss and took the favorable wind conditions, gambling that his defense would do its job.

Both times, the defense forced the Rams to go three-and-out. Both times, the Vikings answered with a go-ahead score. And both times, it was Joseph who set the tone defensively.

The Vikings trailed 15-10 on the first possession of the second half when Bridge­water was intercepted in the end zone for a touchback.

The Rams went immediately to their strength: Gurley. But Joseph broke into the backfield and dropped Gurley for a 2-yard loss.

"I hit the center [Tim Barnes] hard," Joseph said. "When [right end] Everson [Griffen] did his job, Gurley couldn't go outside. He ran to me because he had nowhere else to go."

If Barnes wasn't ready to cast his Pro Bowl vote for Joseph by then, the next snap might have pushed him that way. Literally. Joseph blasted through Barnes and shared an 8-yard sack with safety Andrew Sendejo.

So after the big momentum-shifting interception, the Rams lost 10 yards in three plays and punted. The Vikings answered with a six-play, 60-yard touchdown drive and two-point conversion to take an 18-15 lead.

As for overtime, Zimmer took a huge risk to avoid putting the 18-mile-per-hour wind to Zuerlein's back. Earlier in the game, Zuerlein used the wind to make a 61-yarder.

"It wasn't an easy [decision], I can tell you that," Zimmer said.

Joseph said he "loved" the decision.

"We're just so aggressive right now," he said. "We're just hungry."

Gurley got the ball on the first play of overtime and started eluding would-be tacklers. But his final cut ended with a 6-yard loss into Joseph's massive arms. The Rams didn't gain another yard.

"I just did what they coach us to do: Run to the whistle," Joseph said. "He kept running, went backwards, I made the tackle and here we are now at 6-2. Six and two."