GLENDALE, Ariz. - Although Arizona Cardinals quarterback Carson Palmer was listed as questionable with a sore right passing elbow, there was no question in his mind that he would play Sunday against the St. Louis Rams.
The Cardinals, trying to stay in the hunt for an NFC wild-card berth, needed Palmer, and he came through in a big way.
Palmer completed 27 of 32 passes for 265 yards and a touchdown, finding star receiver Larry Fitzgerald early and often, and the Cardinals cruised to a 30-10 victory over the Rams at University of Phoenix Stadium.
It was the fifth win in the past six games for the Cardinals (8-5), and it keeps their playoff hopes alive, although they are still on the outside looking in.
If they do reach the postseason, they may have to do it without rookie safety Tyrann Mathieu, who suffered a left knee injury in the third quarter and had to be carted off the field.
His status was not immediately known, but it did not look good. Mathieu was tackled awkwardly after fielding a short punt. He seemed to be OK initially, but he collapsed while jogging off the field.
The Rams (5-8) have now dropped two straight since beating the Colts and Bears in blowout victories.
Fitzgerald looked like the perennial Pro Bowl receiver of old, catching a season-high 12 passes for 96 yards and a touchdown. The 12 receptions were one shy of his career high. It was his first double-digit reception game since 2010 and surpassed his previous season high of eight catches for 80 yards achieved in the season-opener against St. Louis.
As good as Palmer and Fitzgerald were, the Cardinals' defense shined just as bright on a brisk day with the retractable roof open under cloudy skies.
Inside linebacker Karlos Dansby stepped in front of a Kellen Clemens pass intended for tight end Jared Cook on the second play of the third quarter and returned it 23 yards for a touchdown.
It was the second interception for a score in three weeks for Dansby, who is back in Arizona after spending the previous three seasons with the Dolphins.
Another veteran free-agent addition, pass rusher John Abraham, came up with a stellar play of his own just six minutes later. With the Rams backed up deep in their own territory, Clemens dropped back to pass but Abraham tackled him in the end zone for a safety and a 23-3 lead.
Abraham added a third sack near the end of the game, giving him 11 on the season to surpass Lawrence Taylor and Leslie O'Neal for ninth on the NFL's all-time list with 133.
Clemens finished the game 16-of-27 for 181 yards with no touchdowns and two interceptions.
Rookie running back Zac Stacy scored on a 1-yard touchdown run for the Rams at the start of the fourth quarter - just the fifth rushing touchdown allowed by Arizona this season.
Cardinals rookie running back Andre Ellington added a 6-yard touchdown run late in the game following a Rashad Johnson interception to complete the scoring.
Palmer was 16-of-17 for 169 yards with one touchdown and no interceptions in the first half, helping the Cardinals take a 14-3 lead.
He led them on an eight play, 80-yard drive to open the game, completing each of his three pass attempts for 43 yards before Rashard Mendenhall ran a power sweep into the end zone for a 3-yard touchdown.
St. Louis countered with a 44-yard field goal by Greg Zuerlien, but the Rams' offense was mostly bottled up by Arizona's seventh-ranked defense.
Palmer, meanwhile, completed his first 11 passes. He thought he had a 17-yard touchdown completion to Jim Dray, but after a review, it was ruled the tight end fumbled the ball inside the Rams' 1-yard line.
That killed an 80-yard drive for Arizona, but it did not deter Palmer and the Cardinals. The defense forced another St. Louis punt and Palmer went right back to work.
He completed seven passes for 48 yards during a 10-play, 80-yard drive just before halftime, capped by a 7-yard scoring pass to Fitzgerald to give the Cardinals an 11-point lead.
It was Fitzgerald's 10th touchdown reception of the season, making him the ninth player in history to record at least five seasons of 10 or more touchdown catches. It was also the 87th touchdown grab of his career, tying him with Andre Reed for 12th place on the NFL's all-time list.
He had eight catches for 71 yards at halftime.
Clemens was 11-of-14 for 141 yards passing in the first half, but the Rams could not run the ball, getting just 28 total yards on the ground against the league's fourth-ranked defense against the run.
NOTES: Rams rookie receiver Tavon Austin suffered a left ankle injury at the end of a 56-yard run in the third quarter. He did not return and his status wasn't immediately known. ... Cardinals kicker Jay Feely, who was 22-of-24 on field goal attempts entering the game, was 0-for-2 on Sunday, missing from 50 and 25 yards. ... The Rams sacked Palmer just once. Robert Quinn had three sacks on Palmer in the season opener, but the one on Sunday was credited to rookie Alec Ogletree.