Stanton will not need surgery on the knee, coach Bruce Arians said Friday.
No timetable is set for Stanton's return, but Arians said there's "definitely" a chance the quarterback could return this season.
"We just don't know when," he said.
Arians said that his quarterback is already wearing a brace and is on crutches and that he will be considered "day-to-day."
"It's just going to be rest and rehab," the coach said. "It's very good news that he's not going to need surgery."
One person familiar with Stanton's MRI told Schefter on Friday that the results were a "huge relief."
The Cardinals host the Seattle Seahawks Sunday night in Week 16 in what could be the deciding game for the NFC West title. This Friday, 10 days before the game, was too early for Arians to determine whether Stanton would be ready to play by then, but he indicated he would be taken aback if Stanton were ready that quickly.
"I wouldn't put it past him, but I would be surprised," Arians said.
Stanton suffered the injury in Thursday night's 12-6 win over the St. Louis Rams on a sack by defensive lineman Aaron Donald with 8:41 left in the third quarter. He hopped off the field on his left leg, not putting any weight on his right knee. After being examined by team doctors and trainers, Stanton was carted to the locker room and eventually was ruled out.
Third-year quarterback Ryan Lindley took over and finished with 4-for-10 passing for 30 yards in his first game action since 2012. Stanton was 12-for-20 for 109 yards before leaving the game.