The Arizona Cardinals, their coach boasted, were much better on that side of the ball.
With the exception of rookie Aaron Donald's sack that injured quarterback Drew Stanton's right knee, "They were not near our quarterback," Arians said after a 12-6 victory Thursday night moved the Cardinals closer to clinching a playoff spot. "Everybody talking all that stuff about how great their defence is, they saw a good defence tonight. It was in red and white."
For the second straight meeting against St. Louis, the Cardinals (11-3) lost a quarterback.
"I'm glad we don't have to play the Rams anymore," wide receiver Larry Fitzgerald said.
They won both times, thanks to a defence that surrendered only 20 points.
Chandler Catanzaro kicked four field goals and Larry Foote had a sack and fumble recovery.
Arians said Stanton had a previous knee injury so will need an MRI exam to determine the extent of the damage.
"We'll take it very slowly with him and see how it goes," Arians said.
The Rams (6-8) were held to Greg Zuerlein's two short field goals and had five three-and-out series in the third quarter. Catanzaro's 23-yard field goal early in the second quarter ended nine quarters of shutout defence by St. Louis, which beat Washington and Oakland by a combined 76-0 the previous two weeks.
The Rams were eliminated from playoff contention.
"We got outplayed and we got outcoached and we just put a bad display out there," tight end Jared Cook said. "It's pretty self-explanatory."
Ryan Lindley was ineffective in his first appearance since 2012 in relief of Stanton, who injured his right knee on the sack in the third quarter, but it didn't matter. The Cardinals lost Carson Palmer to a season-ending knee injury during their 31-14 home victory over St. Louis last month.
Arians opted for Lindley over rookie Logan Thomas.
"It was not a time to put Logan out there," Arians said. "He's going to be a good player someday, but he's not ready for this yet. And Ryan was more than ready."
Kerwynn Williams was the Cardinals' offensive standout with 75 yards on 15 carries. Stanton was 12 of 20 for 109 yards and Lindley was 4 of 10 for 30 yards.
The Cardinals entered tied for the top overall record in the NFC and will clinch a playoff spot if Sunday's Dallas-Philadelphia game doesn't end in a tie, or a Detroit loss combined with a Green Bay victory.
"My first time with 11 wins. I'm happy," cornerback Patrick Peterson said as he walked into the locker room.
Rams players had no apparent protests relating to unrest in nearby Ferguson. Two weeks ago, five players did the "Hands Up, Don't Shoot" pose coming out of the tunnel during pre-game introductions, and last week players wrote "I Can't Breathe!!!" on wrist bands and cleats.
Rams rookie Tre Mason's fumble gave the Cardinals a short field that set up Catanzaro's first field goal. Frostee Rucker punched the ball free and Foote recovered at the St. Louis 27.
It was the first score given up by the Rams since Nov. 23, when San Diego scored the winning touchdown with just over 8 minutes left in a 27-24 victory.
Michael Floyd' 49-yard reception set up Catanzaro's 44-yard field goal that put the Cardinals up 6-3 midway through the second. Catanzaro made kicks of 51 yards and 46 yards in the second half
Arizona committed five penalties on its first two possessions, twice wiping out big gains. Shaun Hill was 4 for 4 with completions of 21 yards to Benny Cunningham on a screen and Cory Harkey for 16 yards to set up Zuerlein's 24-yard field goal in the first. Zuerlein missed an extra-point kick and two field goals inside the 40 last week.
Notes: Fitzgerald was held in check against a team he has dominated, finishing with seven receptions for just 30 yards. Still, at 31 he became the youngest player to 900 career catches. In 22 games against St. Louis, he has 128 receptions and 16 TDs, most against any opponent. ... The Cardinals last won a road game without scoring a touchdown in 1935. ... The Rams led at halftime of their previous five home games this season, two of them losses. ... The Cardinals took the lead in the series, 36-35-2. ... Arizona is 7-0 at home and 4-3 on the road. ... The Rams entered with consecutive wins for the first time this season and are 3-4 at home.
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