An MRI confirmed that Stanton has a sprained knee and is week-to-week, NFL.com's Ian Rapoport reports.

The Cardinals do not believe Stanton's season is over, and the quarterback said he experienced "huge relief" when learning the results of the MRI. However, Stanton still faces an uphill climb to be ready to play Week 16 against Seattle, so it's very possible that either Ryan Lindley or Logan Thomas is forced to start against the Seahawks.

Mike Jurecki of Fox Sports 910 indicates that he is hearing that Stanton suffered a sprained ACL and Grade 2 MCL sprain in Thursday's win over the Rams.

We'll await confirmation of the report, but Stanton's status for Week 16's game against Seattle on Dec. 21 is clearly dicey, with the Cardinals now down to Ryan Lindley (who took over for Stanton on Thursday) and Logan Thomas as healthy QB options, with Carson Palmer on IR.

Speaking after Thursday's game, Cardinals head coach Bruce Arians said Stanton (knee) had already been dealing with an injury in his right knee, prior to exiting Thursday's contest. Arians added that Stanton will undergo an MRI.

The need for an MRI comes as no surprise, and while Stanton's ankle was thought to be the greater concern, he was listed with both ankle and knee issues on the Week 15 injury report. Stanton exited Thursday's game after a third-quarter sack, giving way to Ryan Lindley, who is listed third on the depth chart. Lindley didn't play well in limited action, and the Cardinals might consider going with Logan Thomas for Week 16 against the Seahawks, if Stanton is unable to play. Stanton appeared to be dealing with significant pain, but there's no need for a rash reaction, as the Cardinals will likely have an update by the end of this weekend.

Cardinals head coach Bruce Arians said after Thursday's game that he does not have any idea about the extent of Stanton's right knee injury, NFL Network on twitter reports.

Stanton will presumably undergo an MRI, after exiting Thursday's game in the third quarter. He appeared to be in significant pain, and had trouble putting any weight on his right leg. Ryan Lindley, who handled the final 20-plus minutes, will likely start in Week 16 against the Seahawks, if Stanton is unable to play.

Stanton, who left Thursday's game in the third quarter with a right knee injury, will not return to the contest, Kent Somers of azcentral.com reports.

The news comes as no surprise, given that Stanton appeared to be in a considerable amount of pain. Ryan Lindley is in at quarterback, and he will likely start next week's game against the Seahawks, if Stanton is unable to play.

Stanton left Thursday's game against the Rams with a right knee injury, and he is questionable to return, Kent Somers of azcentral.com reports.

Stanton entered the contest with a minor ankle concern but seemed fine through the game's first 36 minutes. He then took a hard hit on a sack, and was taken back to the locker room shortly thereafter. The Cardinals surprisingly went with Ryan Lindley instead of Logan Thomas, opting for experience over physical talent. If Stanton doesn't return, he'll finish 12-of-20 for 109 yards, with no touchdowns or interceptions.

Stanton (ankle) is active for Thursday's game in St. Louis, Mark Dalton of the Cardinals' official site reports.

Stanton's status as a game manager will face a stiff test against a Rams defensive front that has notched a whopping 13 sacks in the last two contests. Prior to the outburst, though, their secondary was somewhat yielding, giving up 17 touchdown passes in the first 11 outings, including a 48-yard touchdown strike from Stanton to John Brown in Week 10.

Stanton (ankle) is listed as probable for Thursday's contest at St. Louis, Darren Urban of the Cardinals' official site reports.

Stanton is merely a game manager for the Cardinals' offense, but his deep ball has emerged on a weekly basis, translating to 18 completions of 20-plus yards over the past four games. Sure, he's completed 58.3 percent of his passes with four touchdowns versus five interceptions during that span, but the Rams defense has given up 7.4 yards per pass attempt this season, meaning the secondary is susceptible to the occasional hiccup.

Stanton (ankle) was a limited participant during Tuesday's practice.

Stanton has carried a slight ankle ailment over the past couple weeks and given the Cardinals' quick turnaround in advance of Thursday's game versus the Rams, Arizona's starting signal-caller was afforded a lighter practice Tuesday. Nonetheless, Stanton is still expected to play as usual in Week 15 against a familiar NFC West foe. After teammate Carson Palmer (knee) went down in early November versus St. Louis, Stanton entered the game and completed 3-of-5 passes for 85 yards and one touchdown. However, since then the solid yet unspectacular Stanton has totaled four touchdowns and five interceptions over the past four games.

Stanton completed 15-of-30 passes for 239 yards with one touchdown and no interceptions during Sunday's win against the Chiefs.

The definition of a game manager, Stanton was able to sustain drives with an efficient showing on third down. During such scenarios, he was 7-for-10, racked up nearly half of his yards (112, to be exact), and connected with Jaron Brown for a 26-yard touchdown in the third quarter that doubled as the winning score. In addition to the modest passing numbers, Stanton scrambled his way to 17 yards in what amounted to a season-high 141-yard effort for Arizona. With a stingy defense on tap Thursday in St. Louis, though, he must have his wits about him against a pass rush that has generated 13 sacks in back-to-back shutouts of Oakland and Washington.

Stanton (ankle) had an ineffective game during Sunday's 29-18 loss at Atlanta, completing 24-of-39 passes for 294 yards, with one touchdown and two interceptions.

It should have been a favorable matchup for Stanton, but he struggled, not leading Arizona to an offensive touchdown until the final two minutes of regulation. He probably should have had a few more interceptions, as the Falcons dropped a couple of easy picks. It will get tougher for him next week, facing a strong Chiefs' secondary, although the potential return of Larry Fitzgerald (knee) could help.

Stanton (ankle) is listed as active Sunday in Atlanta, the Cardinals' official site reports.

Stanton has been shaky in place of Carson Palmer (knee), but the former's deep ball -- he's hooked up for 18 completions over 20 yards -- have kept defenses honest. If pressed into a corner, owners may be in for a surprise, as Stanton faces down a Falcons defense that has given up 313.2 passing yards per contest with nine touchdowns versus 10 interceptions over the past six games.

Stanton (ankle) is probable for Sunday's game against Atlanta.

Stanton practiced fully all week, so his availability for Sunday was never in question. Playing against a weak Atlanta defense, Stanton might be able to play above his typical production level Sunday, though he's generally still a risky consideration in standard season-long leagues.

Stanton (ankle) practiced in full Thursday, FOX Sports 910 Phoenix reports.

Since Carson Palmer (knee) went down for the season in Week 10, Stanton has helmed the Cardinals' offense, with mixed results. While he's completed 60.3 percent of his passes, he boasts three touchdowns versus three picks across two-plus contests. No matter, he'll attempt to bounce back against a Falcons defense that has allowed three 300-yard passers in the last four games.

Stanton completed 14-of-28 passes for 149 yards with an interception in Sunday's 19-3 loss at Seattle.

Stanton really struggled in a tough environment, although he should have had a touchdown, if not for a dropped pass in the end zone by Jaron Brown right before halftime. He was receiving medical attention on the sideline in the fourth quarter, with an unspecified injury, but he didn't miss any snaps. Assuming there isn't a major injury in play, he'll look to rebound at Atlanta next week.

Stanton completed 21-of-32 passes for 306 yards, with two touchdowns and a pair of interceptions, in Sunday's 14-6 win over the Lions.

It looked like Stanton was going to have a monster game, connecting with Michael Floyd on a pair of first-quarter touchdowns, but he didn't lead Arizona to any points over the final three periods. One of his interceptions came in the red zone, and he missed some throws in the second half, although Detroit's strong defense probably had a lot to do with that. Nonetheless, he did enough to help the Cardinals improve to a league-best 9-1 on the season. In Week 12, Stanton will have a tough test, facing a rugged Seahawks' defense on the road.

With Carson Palmer out for the season with a torn ACL, Stanton will assume the Cardinals' starting quarterback duties, beginning with this coming Sunday's game against the Lions.

Stanton is a priority add for those scrambling to replace Palmer, and an option for those in need of a Week 11 bye week plug-in, or QB depth in general. While his matchup this coming weekend is a challenging one, Stanton could end up putting up respectable fantasy production down the stretch if he establishes a good rapport in the passing game with the likes of wideouts Larry Fitzgerald, Michael Floyd and John Brown, as well as running back Andre Ellington.

Stanton completed 3-of-5 passes for 85 yards and a touchdown in Sunday's 31-14 win over St. Louis. He entered the game in the fourth quarter after Carson Palmer left with a knee injury.

Palmer had to be carted to the locker room, so while it's too early to speculate on the nature of his injury, it doesn't appear to be minor. Stanton tossed a 48-yard touchdown strike to rookie John Brown a few plays after Palmer left, showing off his willingness to challenge defenses. If you're in need of a QB, it wouldn't be a bad idea to grab Stanton, in case Palmer's injury turns out to be serious. The Cardinals have a tough matchup in Week 11, however, facing a solid Lions' secondary.

Stanton's (concussion) teammate, Carson Palmer, worked with the Cardinals' first unit during warmups, Darren Urban of azcardinals.com reports.

The Cardinals elected to have all three of their quarterbacks active for Sunday's game, but based on the look of things in pre-game warmups, the signs point to Palmer (who appeared to be throwing well in advance of the contest) drawing the start, with Stanton in the backup mix.

Stanton (concussion) is listed as active Sunday versus Washington, the Cardinals' official site reports.

After Stanton was cleared of concussion symptoms and Carson Palmer (shoulder) failed to practice in full Friday, Stanton seemed in line to start at QB for the Cardinals. However, Ian Rapoport of NFL Network reported early Sunday that he expected Palmer to get the nod instead, barring the outcome of pregame warmups. The Cardinals' three signal callers (also, Logan Thomas) are active, but coach Bruce Arians has yet to make the final call on the main man under center.