MINNEAPOLIS — The word became official roughly 90 minutes before kickoff.

Dalvin Cook was inactive, and Alexander Mattison would start in his place for the third time in two-plus seasons.

Head Coach Mike Zimmer said confirmation of Cook not being able to suit up because of a Week 2 ankle injury came via text Sunday morning.

Mattison explained his relationship with Cook made him among the earliest to know, but the third-year pro added that the two-time Pro Bowler wasn't trying to apply pressure.

"Just between me and him, I probably found out a little sooner than everybody else. But I prepare every week the same way," Mattison said. "I have a routine. [Running backs coach Kennedy Polamalu] is big on us having our routines. So, going about it that way, having a routine, but just having to take care of my body a little different knowing I have to take all the reps in practice and also going to have to [play the] first snap of the game. But, yeah, just taking it and attacking it the same way I'd attack any other game. Just have to understand, obviously, I'm taking the first rep instead of being ready to go in."

The Vikings erased a 10-point deficit by scoring the game's final 23 points Sunday in a 30-17 win over the Seahawks in Minnesota's home opener.

Minnesota's first offensive snap was a 7-yard gain on a run by Mattison, a solid start for the 2019 third-round pick.

The second? Even better. A screen pass nicely designed popped for 20 yards and included a pancake block of Bobby Wagner by Mattison's former Boise State teammate, Ezra Cleveland.

It sent a couple of messages early: Minnesota planned to run the ball with or without Cook, and the Vikings felt they could slow down some of Seattle's attack with screens.

"I thought it was a big part of us getting started on that first drive, the second play of the game hitting a screen," said quarterback Kirk Cousins, who turned in a gem of a game. "I think we hit a couple others that were big, one of them we couldn't get up on the Mike [linebacker], and he made a great tackle and stopped us, but when you have a strong pass rush that's rushing hard up field, it's great to have that complement to be able to sprinkle that in. Sometimes screens don't hit, but when they do, it's a great thing."

Mattison rushed 26 times for 112 yards, tying a career-high that he set last season at Seattle when he relieved Cook in the second half. He also added a career-best 59 receiving yards on the way to totaling another pinnacle mark with 171 scrimmage yards.

"I was really impressed with what Alex did, not only running the football but in the pass game," Cousins said. "Alex impressed me two years ago as a rookie when he came in – how well he caught the ball, mentally how well he handled all the protections and running the routes. I was impressed today with the way he runs after contact. He really brings his pads and runs with a lot of forward body lean. It makes him tough to bring down, and it makes him a violent ball carrier, which I love to see. He was really good on the screens today, and I was really proud of the way he played."

Replacing No. 33 — and the usually large workload that Cook handles — involved 32 touches, plus other encounters when he blocked Seahawks. Mattison admitted he was already wearing some of the hits he took under his pastel tie-dyed sweat suit.

"Feels a little tough right now, but it's one of those things I love about the game," Mattison said. "Feel every single one of those reps, but they all paid off, and we were able to come out with a victory, so that's all that matters."

Zimmer said Mattison "always runs hard."

"He got many opportunities today. Alex is a good back. He's good in protection," Zimmer said. "He does a nice job in the run game, but the offensive line deserves a lot of credit, as well."

Mattison said Cook "knew I was ready for the opportunity" and told Mattison to "run with it."

"He's with me every step of the way. Come to the sideline, get some advice from him if he saw something," Mattison said. "Most of the time though, he's telling me I was doing exactly what he would do, so that just made me proud to kind of be that little brother in a sense where I'm just there and trying to learn from him, and it prepared me for this moment.

"Being behind him these past couple years, it's been a huge blessing for me and my game," Mattison added. "For us to go out there as an offense, his energy and his presence was felt today even though he wasn't out there."