Sean Mannion will start for the Vikings at Green Bay Sunday.

Vikings Head Coach Mike Zimmer confirmed that Mannion, who was activated off the COVID-19/Reserve list Friday morning, will lead Minnesota's offense in the absence of Kirk Cousins, who tested positive for the virus Friday.

"We hate to see that happen to Kirk, but he's done a lot of great things for us," Zimmer said. "Sean is a really good football player, and we're expecting him to go out and play really well."

Zimmer said there "really wasn't" much consideration given to starting rookie Kellen Mond over Mannion, who has been Cousins' backup all season.

"We knew that Sean was coming back, and Sean is extremely bright, he studies like crazy, he's a great competitor," Zimmer said. "He's put in his time, he's earned this opportunity, and I think he'll do great."

Mannion last played in a regular-season game on Dec. 29, 2019, when he started for Cousins in Week 17. He's been oft-praised by coaches, though, about his football I.Q. and the way he supports Cousins in the meeting room and from the sideline.

Mannion was with the Vikings all of last season as Cousins' backup but signed with the Seahawks in July. When Seattle released the quarterback in September, he re-signed with Minnesota.

Heading into Sunday Night Football against the Packers, Zimmer said the game plan stays "pretty much the same" with Mannion under center.

"Obviously their game plan will change, so we may have to make some adjustments," Zimmer said. "Sean knows the game plan cold. Like I said, he's an extremely brilliant person. He puts in the work every single week like he's going to be the starter. And he is this week."

And speaking of cold, frigid temps are predicted for Sunday night's matchup at Lambeau Field. Regardless of who would have been at quarterback, it will be interesting to see if weather conditions at all affect either team's approach to running the ball or passing it.

"They rush the passer really well, they do a good job in creating sacks, but they cover well, as well. So when a team is trying to throw the ball and do those things, you get more opportunities to do that," Zimmer said. "It'll be a big thing on Sunday night with the weather conditions and the cold. We're going to have to take care of the football and treat it like it's gold."

Despite the last-minute roster changes ahead of a must-win game, Zimmer feels confident in the Vikings chemistry with Mannion.

"I talked to [the players] a couple times this morning, I'll talk to them again tomorrow," Zimmer said. "I think they're going to rally behind Sean. They know how important this game is. They believe in Sean."