TEMPE, Ariz. (AP) -- The Arizona Cardinals' offensive line regressed a bit in Philadelphia after a series of solid performances in a four-game winning streak that preceded the loss to the Eagles.
Next up is a formidable challenge against the fierce pass rush of defensive end Robert Quinn and the rest of the St. Louis Rams.
When the Rams beat Arizona 27-24 in the season opener in St. Louis, Quinn had three sacks, two forced fumbles and four quarterback hits.
That was against left tackle Levi Brown, who since was traded to Pittsburgh. Coach Bruce Arians gave the job to young Bradley Sowell, who has had his hands full against some of the game's top pass rushers.
On Arizona's first offensive series last Sunday, Trent Cole beat Sowell and knocked the ball out of quarterback Carson Palmer's hand, a turnover that led to Philadelphia's first touchdown and the Eagles went on to win 24-21.
Facing Quinn, Arians said, is probably the biggest challenge Sowell has had thus far.
''Even bigger than Robert Mathis (of Indianapolis),'' Arians said, ''because this is a young Robert Mathis. It's a challenge for us as coaches to give him some help somehow, some way.''
Sowell, who barely played for the Colts last season, agreed.
''I think Quinn's a little bigger (than Mathis),'' Sowell said before Wednesday's practice. ''He's maybe a little faster at this point. He's a lot younger, got a little more juice.''
The Rams have more than Quinn, too. On the other end of the defensive line is the formidable Chris Long.
''It's tough every week in this league and this week is extra tough because they've got two of them that are as good as it gets,'' Arizona right tackle Eric Winston said. 'We're going to have to play well. There's no hiding, especially in this offense. Coach Arians throws the ball. He wants to drop back and he wants to get it downfield.''
Palmer needs a clean pocket to be at his best.
''A huge challenge,'' Palmer said of the offensive line's task Sunday against the Rams. ''They have three good pass rushers and they have five or six guys that they rotate in and out and keep fresh and they keep coming. That's kind of what (Rams coach Jeff) Fisher's always done, even when he was at Tennessee. ... They're a very good group and the linebackers are very good, too.''
The Cardinals (7-5) face the Rams (5-7) with no margin for error if they want to stay in the playoff race. The schedule makes it tough for them to catch the two teams ahead of them in the NFC wild card chase - San Francisco (8-4) and Carolina (9-3).
Arians said Sowell is ''a work in progress still.''
''He's still so young,'' Arians said. ''The one thing is he fights. He gets beat, he gets up and he fights. That's all you can ask of a guy.''
Sowell acknowledged his problems in Philadelphia.
''I've been up and down,'' he said. ''I had a span where I was really playing well, and last week I got beat a couple of times. I've just got to try to be consistent.''
As a left tackle, Sowell said, the competition is difficult no matter the opponent.
The Rams are tied for fifth in the NFL in sacks with 37. Quinn's 13 sacks are second only to Mathis' 15 1/2. Quinn leads the league with six forced fumbles.
''Watching him on film, he's really impressive,'' Sowell said. 'He's gone against some good tackles and given some good tackles trouble. You've just got to pick out a technique that you think you need to work on for him. You've got to basically make up your own game plan for him, and either it's going to work or it's not.''
Sowell said he had trouble with the crowd noise in Philadelphia. At least this week, he'll be playing at home.
''In this league at home means the world,'' Sowell said. ''When you can look at your guy and block him rather than looking at the ball and blocking, it's a lot different. But no excuses, I've got to do a better job with noise and stuff. I've done better at home this year.''
Notes: Arizona WR Michael Floyd sat out Wednesday's practice with an ankle injury. RB Andre Ellington, who missed the Eagles game with a knee injury, also didn't practice. Seven other players were limited, including Palmer, who has a sore right elbow.
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