Minnesota had exciting moments in its preseason opener, and quarterback JJ McCarthy put himself in position to possibly unseat presumed starter Sam Darnold. But hold on a minute. McCarthy picked up a sudden knee injury and didn’t practice Monday.

Head coach Kevin O’Connell announced the injury, and NFL Network’s Ian Rapoport reported it by writing “Vikings coach Kevin O'Connell announces that rookie QB JJ McCarthy is dealing with knee soreness and won't participate in tonight’s practice.”

Will injury slow Vikings QB JJ McCarthy's pursuit of starting job?

Minnesota Vikings quarterback J.J. McCarthy (9) looks to pass during the second quarter against the Las Vegas Raiders at U.S. Bank Stadium. TODAY Sports
Jeffrey Becker-USA TODAY Sports

One sad thing for Vikings fans is the timing of the physical setback. With Monday’s practice open to the public, according to Sports Illustrated, it would have been their first chance to get a practice glimpse of the Vikings rising talent. The open practice had been set for Aug. 4, but weather postponed it.

Another down note is the injury came after McCarthy put in an outstanding performance in Saturday’s 24-23 win over the Raiders. In his preseason debut, McCarthy overcame an interception on his first possession and led the Vikings to three scoring drives. Two of those finished with his touchdown passes, coming from 45 and 33 yards away. He finished 11 for 17 for 188 yards. Also, he added two carries for 18 yards.

But most of all, he had O’Connell smiling. O'Connell said McCarthy played well, via Sports Illustrated from The Pat McAfee show.

“For his first time out, there's really not much more you ever want to see than just the guy take the work (over) from the practice field,” O'Connell said. “Obviously, anytime you play a game, preseason or not, in an NFL stadium, you tend to see who guys really are as players.”

JJ McCarthy took advantage of chances to shine

O’Connell said there were many learning moments for McCarthy in the contest.

“What I was most proud of is just the way, even after (he) turns it over early, (he) comes right back and is ripping the ball down the field, standing in the pocket, generating explosives on early downs (and) a couple big third down conversions and got the team in the end zone a couple times there,” O’Connell said. “(I) thought it was a great first start for him.”

But the knee could swing the pendulum back in the favor of Darnold for the Week 1 start. Darnold’s performance didn’t turn any heads as he completed 4 of 8 passes for 59 yards. But he’s the veteran in the room. And for as good as McCarthy has looked, he needs to be 100 percent because the Vikings won’t risk putting him out at less. Not at this point in his career.