Rams defenders celebrate during their 17-3 win over Arizona. (US Presswire)

The Rams rode a dominant defensive performance to a 17-3 win Thursday night over the undefeated Cardinals that put St. Louis above .500 for the first time since November 2006. It was St. Louis’ first home win over Arizona in eight tries. 

Defensive ends Chris Long and Robert Quinn led a fierce pass rush. The Rams (3-2) tore through Arizona’s (4-1) subpar line for nine sacks of Kevin Kolb, and they hit or hurried him 32 times.

Rams quarterback Sam Bradford missed 12 straight throws at one point but threw a beautiful deep ball to put the game out of reach. His 51-yard touchdown to rookie Chris Givens stretched the lead to 17-3 early in the fourth quarter.

Kolb, who has no running game to lean on, has been sacked 17 times the last two weeks.

When the game turned: The second half was a stalemate until Givens put a double move on Cards CB Greg Toler. With time to throw, Bradford lofted a perfect ball for the decisive 51-yard score. The play cemented Givens’ role as the deep threat; he caught a 52-yard pass last week.

Highlight moments: The Rams made two fourth-down stops in the red zone. On the first one, rookie CB Janoris Jenkins closed on WR Larry Fitzgerald and tackled him at the 3.

On one of the Rams’ nine sacks, four defenders met at the quarterback.

Danny Amendola made a one-handed, 44-yard catch on the Rams' opening TD drive before he got hurt on a diving attempt in the second quarter. The injury is feared to be a broken collarbone.

Arizona got a spectacular end-zone interception from Patrick Peterson, who barely got both feet in.

Top-shelf performances:

  • Quinn -- Six tackles, three sacks, forced fumble
  • LB James Laurinaitis -- 10 tackles, sack
  • CB Cortland Finnegan -- 10 tackles, sack
  • Long – Sack, two QB hits
  • P Johnny Hekker -- Averaged 56.9 yards on seven punts
  • Peterson -- INT, five punt returns for 76 yards

What they said about the Rams pass rush: 

Laurinaitis -- "When [the front four] are getting after it like they were tonight, it makes it easier on everyone in the back end. ... We shut down the run game in the first half, and we knew they could pin their ears back in the second half and get after Kolb."

Long -- "We sensed some blood in the water. When that happens as a D-line, you have to get after 'em and finish em off."

What they said about Amendola's injury (feared to be a broken collarbone):

Bradford -- "It's big. I’m not going to try to downplay it. He’s a big part of this offense. A lot of what we do runs through him. ... But I feel confident enough in the guys we have this year."

Numbers you should know: The Cardinals still have not gained 300 total yards in any game; they had 282 Thursday night … Arizona rushed 17 times for 54 yards (2.6 ypc) … Bradford was sacked only once. But without Amendola, the Rams struggled on third down, going 4 of 14 …Steven Jackson ran for a season-high 76 yards on 18 carries (4.2 ypc).

Rams S Quintin Mikell took a knee to the head and was down on the turf for several moments before being able to walk off.

Rams backup LB Mario Haggan and special-teamer left with a thigh injury.

Cardinals RB Ryan Williams took a brutal hit on a running play and was down on the turf briefly. He walked off under his own power. The team called it a left shoulder injury.

Cardinals LB Reggie Walker left after taking a blow to the head.

Cardinals CB Greg Toler appeared to hurt his hamstring on Givens’ 51-yard TD catch.

Going forward: If the Cardinals can’t improve their offensive line, they’ve got to adjust their protection schemes or at least find a running game. Bobby Massie and D’Anthony Batiste were exposed again as the NFL’s worst tackle combo. Arizona hosts Buffalo on Oct. 14.

The Jeff Fisher era has started better than any Rams fan could have dreamed as the team heads into an Oct. 14 game at Miami. However, if Amendola is out for an extended period, Bradford needs to develop better chemistry with the other receivers. Bradford finished 7 of 21 for 141 yards and two touchdowns, with one interception.

Get more Rams updates and analysis from Larry Hartstein @CBSRams.