TEMPE, Ariz. (AP) For the second time in his three-year NFL career, Tyrann Mathieu is out for the season with a torn ACL.
Coach Bruce Arians revealed the extent of the injury at his Monday news conference.
The popular safety/cornerback - ''Honey Badger'' to his fans - injured his right knee after intercepting a pass in the final minutes of Sunday night's 40-17 victory at Philadelphia.
He tore the ACL and LCL in his left knee 13 games into his rookie season in 2013.
No longer having to wear the knee brace that slowed him in 2014, Mathieu was having an outstanding season and was the NFC defensive player of the month for November. He is third on the team in tackles with 89 - behind Deone Bucannon's 110 and Kevin Minter's 91 - and is tied with safety Rashad Johnson for the team lead in interceptions with five.
''He set goals and he was attaining them,'' Arians said. ''I thought he should be right there with Patrick (Peterson) for (NFL) defensive player of the year. I don't think there was any doubt he was having that type of season, and it's a shame with two games left. And it's always a non-contact injury when these things happen.''
It was after that fifth interception that he came down awkwardly on his right leg and fell to the turf. He flexed his injured leg as he lay on his back, then limped off the field with 2:33 to play.
There had been some optimism because Mathieu was walking without a limp after the game.
''He felt very relieved because he was walking fine (after the game),'' Arians said. ''He's still walking fine, it's just the MRI says differently.''
The victory clinched the NFC West title for the Cardinals and gave them their first 12-win season in the history of a franchise that dates to 1920.
''I'm very happy for obvious reasons,'' Arians said, ''other than it's very bittersweet when you lose a guy like Ty.''
Arians has said he's never been more proud of a draft pick than the one the Cardinals used to select Mathieu in the third round in 2013. It was considered a significant risk at the time.
Mathieu was a Heisman Trophy finalist when he was at LSU, but was kicked off the team and out of school for marijuana-related issues. He was out of football in 2012 and the contract he signed with Arizona included requirements for a large number of drug tests.
But he's never been a problem since the day he arrived. Helped by his LSU teammate Peterson, he emerged as a charismatic team leader, a high-energy player on the field and a highly accessible one off it.
Arians acknowledged that Mathieu was a favorite player. The coach was kicked off his team in high school.
''We have a little different bond just because where he came from, where I came from and I've just gotten real attached to him,'' Arians said. ''I love the player. but I love the person more.''
The coach said surgery will come in a couple of weeks after swelling in the knee subsides.
The Cardinals have no time to dwell on the impact of the Mathieu injury. They can clinch a first-round playoff bye with a victory at home against Green Bay on Sunday.
''We go to work Wednesday,'' Arians said. ''Nothing's changed. They're not going to cancel the game. We've been through this many times.''
Jerraud Powers will move into Mathieu's nickel cornerback spot, Arians said. That would mean Justin Bethel taking Powers' spot as outside corner when the team is in its nickel configuration.
''We'll see what roster moves we make, if we make any,'' Arians said.
Johnson, who missed Sunday's game with an ankle injury, should practice this week, the coach said.
Tony Jefferson and recently-signed D.J. Swearinger are the other safeties on the roster, along with Bucannon, who is listed as a safety but usually lines up in an inside linebacker spot.
''Tony played well, D.J. played well,'' Arians said. ''Hopefully we'll get Rashad back and just keep moving.''
Notes: Arians said quarterback Carson Palmer's right index finger was dislocated, but that it was popped back into place and he should be fine. ... Running back Andre Ellington was a game-time decision, but wound up sitting out his third straight game with turf toe. ''We're hoping we can get a different shoe on him that's comfortable,'' Arians said.
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