GLENDALE, Ariz. — Practice makes perfect.

That’s that old adage that we’ve been led to believe for years. Yet, it didn’t apply to Arizona Cardinals quarterback Carson Palmer, who completed 27-of-32 passes for 269 yards and a touchdown in his team’s 30-10 win over the St. Louis Rams at University of Phoenix Stadium Sunday.

The catch? Palmer didn’t throw one pass in practice leading up to the game. The veteran injured his elbow early in the Cardinals’ Week 13 loss at Philadelphia, but gutted it out.

So does this mean a new regimen for Palmer as far as game preparation?

“No, no, I need to practice,” Palmer said following the game. “I didn’t throw one ball and I was definitely worried about that, but that was the plan from (head athletic trainer) Tom Reed and his staff.

“They’re the best in the business, we’re fortunate to have them because he had a plan from Monday on and we stuck to it. I had one-hundred percent faith and trust in him that he knew what he was doing and he and his staff got me ready to play.”

Palmer was more than ready to play — he completed his first 11 passes of the game and finished up the first half by connecting on 16-of-17 throws for 169 yards and a 7-yard touchdown to Larry Fitzgerald.

“I felt great all day,” he said. “When Tom told me I’d be fine, I had to just stick with what he was saying — I knew I was going to play all week.”

Palmer’s completion percentage of 84.4 was the highest of his career, bettering a mark of 84.2 percent (32-of-38) he had in a 35-6 win over Tennessee in November of 2007 when he was with Cincinnati.

It’s also the second-best single-game completion percentage posted by a Cardinals quarterback — only Kurt Warner’s 92.3 percent set on September 20, 2009 at Jacksonville is higher.

Sure, Palmer was on, but he also had arguably his best pass protection of the season aiding the cause. In 32 dropbacks, Palmer was sacked just once and hit two other times. That’s a far cry from the lack of protection the quarterback had in the first meeting between the two teams in Week 1 when he was sacked four times and hit on six other occasions.

“We had a great game plan protection-wise, I think maybe I was sacked one time,” he said. “That defense rarely ever gets only one sack and they always get quarterback pressures and quarterback hits and knock-downs, but the protection was phenomenal.

“You’ve got one of the best pass rushers in the game in Chris Long, who’s right behind (Robert) Quinn and the two guys inside are very good and we did a great job up front.”

The Rams came into the game ranked fifth in the league with 37 sacks, and to Palmer’s point, it was only the third time all season St. Louis registered only one sack.

“These guys are really good on defense and they’ve been playing really, really good,” Palmer said. “They’ve beaten good teams, they’ve had big wins. They handled Indianapolis with ease, they handled Chicago with ease.

“When you turn on the film, that’s a very good defense. It’s young, it’s inexperienced and it’s really going to get better with time, but you don’t turn the film on an look forward to playing against these guys.”

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