TEMPE, Ariz. (AP) Through three games, Arians-ball sure looks like a force to be reckoned with in the NFL.

The Arizona Cardinals' running game is clicking behind late signee Chris Johnson, Larry Fitzgerald is off to the best start of his already spectacular career, tight ends are making big plays, John Brown is speeding past defenders.

At the center of it all is Carson Palmer, a 35-year-old quarterback at the top of his game.

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With a defense that's pitching in with touchdowns - and a safety - and rookie David Johnson returning a kickoff 108 yards, the Cardinals have outscored three opponents 126-49. No one comes close to that plus-77 differential. New England is second at plus-49.

Arizona is the fourth team in NFL history and first since 1968 to score 17 touchdowns in the first three games. The Cardinals have not trailed once this season.

Yeah, the competition hasn't been the greatest - New Orleans, Chicago and San Francisco are a combined 1-8. But this is a self-assured bunch in Arizona.

''We are confident because we are good and we know it,'' Palmer said.

Acquired from Oakland for next to nothing three years ago, Palmer needed time to learn the intricacies of coach Bruce Arians' offense, but he's got it down now.

He has won his last nine starts, longest active streak in the NFL, and is 16-2 in his last 18 games.

''Right now he is playing as well as anyone I have ever had,'' Arians said.

The quarterbacks Arians has had include Andrew Luck, Ben Roethlisberger, Peyton Manning.

But let's not get carried away, Palmer said. It's just three games.

''I want him to say that in 14 weeks when we are going into the postseason,'' he said. ''Obviously he's a very well-respected coach, a good offensive-minded coach. Anytime anybody says something like that about you it's flattering, but we are just getting started and we have a lot of football to play.''

The most important component in the offensive success is the running game. Last year Arizona ranked last in the NFL at 3.3 yards per attempt. This year, the Cardinals have topped 100 yards rushing in each game and are averaging 4.2 yards per carry. With Andre Ellington - who could be back this Sunday - sidelined with a sore knee, Chris Johnson, signed off the street late in the preseason, has 219 yards in 52 carries. He had a 40-yard reception in last Sunday's 47-7 rout of San Francisco.

''That's the main reason for all of it,'' Arians said. ''The play-action pass, the chunk plays, all come off the running game. The red zone success obviously comes from running the ball.''

The Cardinals have 11 touchdowns in 12 trips to the red zone. The one time they failed came when the half ended against the 49ers and they settled for a field goal.

The offense hasn't been at full strength, either.

Ellington, a dynamic receiver as well as runner, was hurt in the opener and missed the last two games with a sore knee. Left guard Mike Iupati, Arizona's main free agent signing, has yet to play after having surgery to repair a meniscus he tore in training camp. Both practiced on a limited basis Wednesday and could be back for Sunday's home game against St. Louis.

Arizona fans remember with dread the St. Louis game in Arizona a year ago. Palmer was asked about that.

''What happened the last time we played them?'' he asked with a slight smile.

What happened was the premature end to what had looked to be a big season. Palmer, stepping away to avoid the Rams pass rush, landed awkwardly and tore the ACL in his left knee. The Cardinals won that game to go 8-1. They finished 11-6 and, down to a third-string quarterback, managed virtually no offense in a wild card playoff loss at Carolina.

Now a healthy Palmer and Fitzgerald - a pair of 30-somethings - are the Cardinals' chief offensive threat.

Transferred to the slot position when Arians arrived, Fitzgerald has never had better numbers through three games - 23 catches for 333 yards and five touchdown, an average of 14.5 yards per catch. He's also, Palmer said, the best pass-blocking receiver in the NFL.

''I think what gets lost in the shuffle with Larry is that he's only 32,'' Palmer said. ''People act like he is 36. He has been playing at a high level for such a long time and you feel like he is an older player. At 32, I think he is in his prime.''

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