Pass protection remains Adrian Peterson’s personal kryptonite, but Vikings coach Mike Zimmer said the old dog is eager enough to learn this new trick of keeping quarterback Teddy Bridgewater upright.

“Honestly, Adrian only had one protection problem [Sunday],” said Zimmer, presumably referring to Peterson’s missed block on safety T.J. Ward, whose strip-sack near midfield clinched Denver’s 23-20 victory with 29 seconds left in the game.

“But other than that, he did a good job in all of his protections. He’s working very hard at it. We kept him in there on some third downs this time, so we’ll keep going with it.”

Unlike some star running backs, Peterson’s effort level in the dirty work of pass protection is saluted by the coaches who are trying to make him better at it. And, remember, Peterson has played only five games for this current staff.

“The thing about Adrian is that he doesn’t just say, ‘Hey, I’m a running back, I don’t want to work on it,’ ” Zimmer said. “He wants to work on this. He wants to be out there as much as he possibly can, so he’s committed to becoming a better pass protector, and I believe he is.

“He’s working very hard at it, and knowing which guys to block and how to block them. There were a couple times he had Von Miller, a couple times he had [DeMarcus] Ware.”

Rating Kalil, Clemmings

According to Pro Football Focus, rookie right tackle T.J. Clemmings gave up two of Denver’s seven sacks and four quarterback hurries. Meanwhile, left tackle Matt Kalil surrendered two quarterback hits, bringing his total to five on the season.

Zimmer was asked if the coaching staff could have given Clemmings more help in pass protection.

“We did help him quite a bit,” Zimmer said. “There are some times some guys are going to have to line up and play. And there were some times T.J. blocked him. But the times he didn’t block him, that’s what shows up.”

As for Kalil, Zimmer remains impressed overall after last year’s struggles.

“Matt did good,” he said. “He got beat on one game over there, but I thought overall he held his own against Ware. And there were times we helped him, too, but he had a fair amount of one-on-ones. He went to the wrong guy one time, causing an issue.”

Zimmer said the Broncos blitzed more than the Vikings expected.

“We had a couple mental errors, we had a couple guys get beat, so it was a combination of things,” he said. “I thought Teddy did a good job of getting the ball out, but there were a couple of times where we weren’t able to adjust the protection because of some of the movement things that we had going on.”

Run-pass script flipped

Yes, the Vikings were aware they had Peterson and the league’s No. 3-ranked running attack. No, it wasn’t their intention to throw the ball 20 more times (41) than they ran it (21) on Sunday.

“No, not really,” Zimmer said. “The script didn’t call for quite that many. But sometimes that’s the situations that you get into. We were aware of who was in the ballgame for them, and we were going to throw the ball when they weren’t in the ballgame. So some of those times we get off the script because of that.”

Five fail on long run

On Sunday, Zimmer took the blame for making a bad defensive call on the 72-yard touchdown run by the Broncos’ Ronnie Hillman.

“I’ll bet you I call myself a few names probably 20 times a game, [saying] ‘You could have called a better call here’ or ‘I thought they were going to do this.’ I don’t necessarily think it was the best call at that particular time,” Zimmer said.

But …

“We did not execute,” he said. “We had about one, two, three, four, five guys that did not execute.”