TEMPE, Ariz. (AP) A severe concussion has ended John Abraham's season, and perhaps his career.
Arizona placed the 15-year NFL veteran on injured reserve on Friday.
''You feel bad for somebody who it's probably the end of their line,'' coach Bruce Arians said.
The 36-year-old outside linebacker sustained a concussion in the season opener against San Diego. He left the team briefly after that, reportedly contemplating retirement, before making an attempt to return this week.
`I think the concussion had a part to do with the depression and everything that went on last week,'' Arians said. ''He was excited and ready to roll and hoping to get the OK from the doctor, then to get that kind of news was real hard.''
The extent of the injury became apparent in a concussion test Abraham took on Thursday.
''The concussion protocol really did its job coming back finding a couple of problems,'' Arians said. ''The doctors feel that he should shut it down for at least a year. We're glad we caught it now and not later.''
Asked what those problems were, the coach said he wasn't smart enough to know what ''all those words'' mean, ''but it's not good.''
It's the latest in a series of problems to hit the Cardinals.
Quarterback Carson Palmer is out with a nerve injury in his shoulder. The team lost defensive tackle Darnell Dockett for the season with a knee injury in training camp.
Then this week, backup running back Jonathan Dwyer was arrested on domestic violence charges. The Cardinals quickly placed Dwyer on the non-football illness list, ending his season.
Abraham is the NFL's active career sacks leader with 133 1/2, ranking him ninth on the league's all-time list. He had a team-high 11 1/2 sacks with the Cardinals last season and is in the second year of a two-year contract with Arizona.
Abraham had four forced fumbles last season, giving him 48 for his career, tied with Jason Taylor for most in NFL history.
Outside linebacker Lorenzo Alexander said the team will miss ''just the football experience, a guy that's played in the league for 15 years and played at that high level.''
Arians said the team will miss Abraham's leadership, too, calling him ''an extra coach.''
Tight end John Carlson, who has had his own concussion issues, noted how the NFL's attitude toward those injuries has changed.
''That's an example of the league being proactive and looking after a guy's interests,'' Carlson said. ''I appreciate that. There's been such a shift in recent years in the league, starting at the top and that's a great thing that they're looking after his long-term health.''
Abraham had a tumultuous early season with Arizona.
He arrived late to training camp, later confirming that he had been undergoing rehabilitation for an alcohol issue. He was arrested in suburban Atlanta in June and accused of drunken driving.
Abraham played six seasons with the New York Jets and seven with the Atlanta Falcons before signing with Arizona as a free agent.
Originally, Abraham was to be only a pass-rush specialist with the Cardinals, but he moved into a full-time role when Arizona lost starting linebackers Sam Acho and Alexander to injury against New Orleans in the third game of last season.
Abraham went on to be one of the top players on a defense that ranked sixth overall in the NFL, earning his fifth Pro Bowl appearance.
Arians said Acho, Alexander and recent signee Thomas Keiser will rotate at Abraham's position.
The Cardinals also re-signed punter Drew Butler because regular punter Dave Zastudil still is nursing a sore groin. Butler punted in both of Arizona's games but was cut Tuesday.
Butler had a punt blocked in each of his two games with Arizona, but Arians said neither was the fault of the punter. The four punts he did get off averaged 54.5 yards per kick.
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