Arians said he made the decision after watching the game film of Sunday's 20-15 loss to Washington.
"It is no fault of Blaine," Arians said. "I think Blaine is going to be a hell of a player, but Drew already knows all those scenarios. He's healthy enough now and it's just a matter of getting those touchdowns that are there from experience, and trying to win this game.
"But it is no way an indictment on Blaine. I think he's played his ass off for [five] weeks."
Stanton, who injured his knee in November, is healthy enough to be mobile if necessary, Arians said.
"If he weren't, I wouldn't make the switch," Arians said, adding that Stanton knows the offense "inside and out."
"Certain things that come up during the game in critical situations, he's been in it and knows it," Arians said.
Gabbert went 2-3 after replacing Stanton as the starter in Week 11; Stanton suffered a knee injury the week before. Gabbert threw for 1,086 yards, six touchdowns and six interceptions while completing 55.6 percent of his passes.
The offense, however, has stalled recently. The Cardinals (6-8) haven't scored a touchdown in the past 10 quarters. Arians felt Gabbert made "some poor decisions" in Sunday's loss to Washington, in which Arizona went 0-for-6 in the red zone.
After he watched the film, Arians felt the Cardinals should've scored on at least four trips.
During a radio interview on Arizona Sports 98.7 FM early Monday morning, general manager Steve Keim said Sunday's game will go down as one of the "more frustrating" of his tenure as Arizona's general manager, which started in 2013.
"It was a frustrating game. [I'm] disappointed," Keim said. "The fact that we were eliminated from playoff contention, you know, again, is a disappointment and I apologize to our fans, everybody in our organization, and moving forward we have a lot of work to do. It's going to be a busy offseason.
"We'll continue to evaluate this team the last two games. I promise, the product on the field in 2018, we'll finish much stronger."
Arians said the Cardinals won't tank the last two games. "We're not going to throw our hands up and say, 'Hey, let's lose the games and get a better draft pick.' That's all bulls--- to me," Arians said. "We're going to take the guys we think can win this game and go win this game."
The move comes two weeks after Arians said a long-term deal for Gabbert "could possibly happen." Arians also said how Gabbert finishes this season will factor into his evaluation of Gabbert as a potential long-term answer in Arizona.
That evaluation process has been difficult for Arizona because Gabbert has been playing with a slew of backups. Four of the five starting offensive linemen Sunday in Washington were backups. He hasn't played with running back David Johnson. Adrian Peterson was put on injured reserve this week. That made it harder for Arians to assess Gabbert and the offense in general.