Sam Darnold to start at QB in Vikings' preseason opener

EAGAN, Minn. -- The Minnesota Vikings will start quarterback Sam Darnold in Saturday's preseason opener against the Las Vegas Raiders .

Darnold has taken nearly all of the first-team reps during training camp, after the free agent departure of incumbent Kirk Cousins , and is the likeliest candidate to open the season as the Vikings' starter.

Vikings coach Kevin O'Connell has not yet confirmed that, however, and said he is looking forward to seeing "a significant amount of work" Saturday from rookie J.J. McCarthy after Darnold's stint.

"Hopefully [McCarthy will] apply some of the things that he's been doing really well, just as Sam has every day in practice," O'Connell said Thursday. "It's been a really good start to the process for all of those guys."

If time permits, second-year quarterback Jaren Hall will finish the game. Veteran Nick Mullens will also be available if needed.

Receiver Justin Jefferson and safety Harrison Smith are not scheduled to play, but otherwise, O'Connell said, the majority of players on the roster will appear.

The Vikings are entering a crucial stage for finalizing their early-season plans at quarterback. They'll travel to Cleveland next week for two days of joint practices with the Cleveland Browns .