EAGAN, Minn. -- The status of J.J. McCarthy is in question after tests revealed the Minnesota Vikings rookie quarterback has a tear in the meniscus of his right knee, with a final determination to be made once he undergoes surgery this week.

Vikings coach Kevin O'Connell confirmed the injury Tuesday, saying it occurred during Saturday's 24-23 preseason victory over the Las Vegas Raiders. McCarthy threw the second of his two touchdown passes on his final play and left only after he played the 30 snaps O'Connell planned for him to take.

McCarthy did not mention any pain or soreness until reporting it Monday to team medical officials. In a post on X, McCarthy said: "Love you Viking nation. I'll be back in no time. Amor fati," referencing the belief that one should appreciate all experiences in life regardless of whether they are pleasant.

Doctors will decide during surgery whether McCarthy needs a trim of the meniscus -- which could allow him to return this season -- or a full repair that could sideline him until 2025.

"That's totally, totally a medical decision," O'Connell said. "Certainly, what's best for the long-term health of J.J. McCarthy will be the priority. I don't have that answer and really won't be a part of determining that answer. ... I have total complete trust in our medical staff and also the people that will be performing the procedure."

The news of McCarthy's injury only further ensures that veteran Sam Darnold, who signed a one-year contract worth $10 million in March after spending 2023 as a backup with the San Francisco 49ers, will be the Vikings' starting quarterback in Week 1 and likely beyond.

Darnold has taken all but two of the Vikings' first-team offensive snaps during training camp and also started Saturday's game. McCarthy's performance Saturday likely meant he would begin to take more first-team snaps in practice, but there was no indication that O'Connell was considering the former Michigan star as a viable option for Week 1.

Darnold, who has looked increasingly sharp as training camp has progressed, completed four of eight passes Saturday for 59 yards. The other two quarterbacks on the team's roster are 2023 holdovers Nick Mullens and Jaren Hall.

"Sam's had a really good camp and my confidence level in Sam is very, very high at this point," O'Connell said, "and looking forward to seeing him continue his progression that we've had for him throughout the early part of camp into that first preseason game. ... 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."

The Vikings selected McCarthy with the No. 10 overall draft pick this year after parting ways with incumbent Kirk Cousins, who joined the Atlanta Falcons in free agency.

McCarthy had made progress since an uneven performance in spring OTAs and minicamp, and he remained in Minnesota during the early part of the summer to refine a set of adjusted footwork and other mechanical changes the team had recommended.

McCarthy maintained a steady approach throughout training camp over to his preseason debut, when he replaced Darnold after one series against the Raiders. The game began inauspiciously when McCarthy threw an interception to end his first series, but he rallied to throw touchdown passes of 45 and 33 yards in the third quarter, finishing the day with 11 completions in 17 attempts for 188 yards.