PITTSBURGH — Vikings replacement quarterback Case Keenum converted the opening third down. Running back Dalvin Cook firmly cut toward left tackle for an eight-yard gain.

Then the yellow flags started flying.

Cook’s run was called back because of left guard Nick Easton’s holding penalty, the first of 11 accepted penalties (two declined) against the Vikings — costing them 131 yards on both sides of the ball in Sunday’s 26-9 loss to the Steelers. It was just the fourth time under coach Mike Zimmer the Vikings were penalized at least 10 times.

Two of those penalties were holding calls on Easton.

“I’m not happy with myself on that,” Easton said. “I thought one of them was iffy and the other one I definitely held.”

Culprits were spread across the Vikings depth chart. Center Pat Elflein was the only Vikings offensive lineman not flagged on Sunday. In all, nine different Vikings were penalized. That’s not counting the two declined penalties, including an early jump from defensive tackle Tom Johnson giving Steelers quarterback Ben Roethlisberger the green light to unleash a 51-yard deep ball to Martavis Bryant.

“We have been pretty good with penalties,” Zimmer said. “We were undisciplined today with some of the things we did. We jumped off sides a couple times and had a couple pass interferences.”

Trae Waynes had perhaps the most backbreaking penalty. The third-year cornerback was pulled from the game after he interfered with Bryant on another deep shot from Roethlisberger. Instead of third-and-22 after the incompletion, Waynes was flagged for a 49-yard pass interference that put Pittsburgh at the Vikings’ 12-yard line. Three plays later, Roethlisberger flipped a touchdown pass to JuJu Smith-Schuster to give the Steelers a 14-0 lead.

“We can’t have penalties like that to win games,” Zimmer said. “Big plays and penalties.”

Waynes wasn’t alone on the defensive blunders. The Steelers’ first three scoring drives, counting for 17 points, were all boosted by Vikings penalties.

Cornerback Xavier Rhodes, given the tough task of shadowing Steelers star Antonio Brown all day, got caught grabbing Brown’s jersey for a 22-yard pass interference penalty. Rhodes’ flag was only possible on that Steelers drive because veteran defensive end Brian Robison made a rare gaffe when he bit on Roethlisberger’s hard count on fourth-and-1 two plays prior.

Another veteran, cornerback Terence Newman, was popped for defensive holding in the fourth quarter that wiped out a third-down stop. The Steelers picked up another three points when Johnson was flagged for lining up over center on a missed 51-yard field goal attempt. Steelers kicker Chris Boswell made the ensuing 46-yard attempt.

“This happens,” defensive end Everson Griffen said. “Guys want to make plays. Guys want to get off the ball. Help the team win. Sometimes you get caught in the act. It’s one game.”