Josh Rosen was picked by the Cardinals 10th overall in April's draft as the team's quarterback of the future.

The future turned out to be late September.

Coach Steve Wilks decided Monday that Rosen was now the team's starting quarterback, with Sam Bradford moving to the bench.

"It's all a process," Wilks said. "He's going to have some growing pains -- that happens as a rookie. But you'll see some great things from him as well."

Asked if Rosen was the starter for the balance of the season, Wilks said he once had made the point that it had been Bradford's job to lose and now "I'm saying the same exact thing about Josh Rosen."

Rosen completed 4-of-7 passes for 36 yards and an interception in his brief appearance during the 16-14 loss to the Bears Sunday. Wilks had decided, after Bradford's third turnover, to make the change. The turnover – and telling Rosen – came with more than 11 minutes left in the game. But the Bears drove down the field with a nearly-seven-minute possession to not only kick the go-ahead field goal but put Rosen in a tougher spot for his debut.

Wilks said he was happy with the fast start of Bradford and the offense in generating 14 points in the first quarter, but then the offense got "stagnant." The turnovers also became costly. Bradford's last, a fumble when the Cards were already in field-goal range, was the breaking point.

"There are definitely no excuses," Bradford said Sunday of his performance this season. "I came out and didn't play my best."

Wilks said Bradford took the demotion in stride.

"Sam Bradford is a pro," Wilks said. "He's going to do everything he can to help Josh, as he was before."

Rosen 's confidence is part of the allure to put him in. Wilks said Rosen has the right demeanor to step in as a rookie, that the game "isn't too big for him."

Rosen is the final rookie QB of the "big four" top 10 picks to be moved into the starting lineup. The Jets installed Sam Darnold as their starter to begin the season, Josh Allen was promoted after Week One by the Bills, and Baker Mayfield earned the nod this week after leading the Browns to a comeback win last Thursday.

"I just wanted to go down and get a field goal and try to win the game," Rosen said after the game Sunday. "It didn't happen, unfortunately, but we've got a long season, and hopefully I'll find my groove."

In the few snaps he played, Rosen showed his accuracy and command of the huddle, Wilks said. His mobility gives the Cards' offense an asset they do not have with Bradford, and Wilks said that could lend itself to more rollouts or bootlegs in the game plan.

"I trust Josh," running back David Johnson said. "He's a good quarterback. I like Sam. He's a great quarterback for us. I can't really focus on quarterbacks. I've got to focus on our (running backs) room."

Wilks did not commit to a backup, saying he'd announce later in the week whether Bradford or Mike Glennon would now be No. 2. It would make a difference in Bradford's contract, since the veteran reportedly has active-per-game bonuses.

But that has nothing to do with the rookie with the starting job.

"Josh plays with a lot of confidence," Wilks said. "I think he gives an opportunity to be successful. When you look at the situation when he went into that (Bears) game, I didn't have a problem because again, he is confident in what he is doing."