Rookie quarterback J.

J.

McCarthy will miss the entire season after undergoing knee surgery on Wednesday.

McCarthy tore the meniscus in his right knee during the Vikings’ preseason opener on Saturday, a 24-23 win.

McCarthy played 30 snaps and threw a touchdown pass on his final play of the game.

On Tuesday, Minnesota coach Kevin O’Connell said doctors would determine during surgery whether McCarthy needed a meniscus trim—which would have allowed him to return this season—or a full repair.

The surgery revealed McCarthy needed the full repair, sidelining him until 2025.

McCarthy, 21, was the 10th overall pick in April’s NFL draft.

He spent three years at Michigan, where he went 27-1 and led the Wolverines to a national championship last season.

Minnesota drafted McCarthy after moving on from Kirk Cousins, who they did not re-sign this offseason after he spent six years with the team.

McCarthy was the first QB Minnesota had selected in the first round since Teddy Bridgewater in 2014.

Sam Darnold, the No.

3 overall pick in the 2018 draft, is expected to be the Vikings’ starter in McCarthy’s absence.

“Sam’s had a really good camp, and my confidence level in Sam is very, very high at this point,” O’Connell said this week.

“I’m really looking forward to Sam’s continued growth and success in the offense, and I know his teammates and the rest of the coaching staff have been really enthused by what Sam’s done.

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