ARIZONA — The Arizona Cardinals will not see Sam Darnold on Sunday.

The Seattle Seahawks are ruling Darnold out with a quad injury ahead of Week 9's meeting at Lumen Field. Drew Lock will start in his place.

The Cardinals previously saw Lock in their Week 2 loss at State Farm Stadium, where Seattle's offense put up 381 total yards and 30+ points in a 31-7 blowout over Arizona.

Prior to that matchup, Arizona head coach Mike LaFleur gave a glowing review of Darnold.

"Sam's a great quarterback. Obviously, I'd say I know Sam a little bit better than Drew because I did have, I guess you could say, a month or so with him even though he wasn't in the building in New York. I've always really respected him dating back to USC. Understanding that he was a young quarterback going through it," said LaFleur back ahead of Week 2.

"Every situation's different by the quarterback and by the club, and he got himself in a very stable situation. I think starting in San Francisco, Minnesota, and then obviously in Seattle. It's not shocking that they got the result they did last year. They are, in my opinion, the best coached team in football. I think they have the best defense in football. In my opinion, they have a really, really good quarterback with it. Yeah, he's down this week, but again, like I just said with Drew, the moment's not too big for him. I think he's a good quarterback who's played a lot of good football."

Now, Lock is set for his third start of the season.

The Seahawks are 4-4 and are have lost their last three-of-four meetings entering Week 9. They're also playing on a short week after featuring on Monday Night Football.

When Lock started for Seattle, he orchestrated a fairly efficient game — going 19/26 passing for three touchdowns and no interceptions. He was also sacked only once by the Cardinals' defense.

Darnold has struggled in 2026, so this might not be a bad switch for the Seahawks' offense — especially if he can again take advantage of a Cardinals defense that's allowed five 30+ point outings in their last six games.

Arizona's fresh off a Week 8 upset over the Dallas Cowboys and are hoping to string together consecutive wins for the first time all regular season.

ESPN's football power index gives the Cardinals just a 17.9% chance to win against the Seahawks.