Richie Incognito was a third-round draft pick by the Rams in 2005. (Tom Szczerbowski/Getty Images)

Claiming he was told his “liver and kidneys are shutting down,” Richie Incognito said Tuesday that he was retiring from the NFL. Over a 12-year career, the Buffalo Bills guard came to be regarded as one of the league’s best run-blockers, but he was also frequently criticized for his behavior and spent a season and a half out of the NFL for his role in bullying a teammate.

“I’m done,” Incognito said Tuesday on Twitter, tagging the NFL Players Association and its assistant executive director of external affairs, George Atallah. The 34-year-old lineman also told the Buffalo News, “I’m done, that’s it,” and said he’d notified the Bills of a decision he’d reached “in the last couple days.”

“It’s been a long career,” the four-time Pro Bowler told the News from his home in Arizona. “My liver and kidneys are shutting down. Nothing I can’t restore with some balance, but the stress is killing me.”

He said that during a recent visit to a doctor, he was told, “Listen, the stress is killing you, what are you doing?” and he replied, “Listen, I’m just doing what I love, and that’s playing football.”

“So that’s why I’m done,” Incognito said. He added that some specialists he’d seen informed him that as a result of his “high-carbohydrate, high-protein diet,” his liver and kidneys were not functioning very well.

Incognito reportedly denied that he was simply “trying to negotiate” with the Bills, who compelled him to take a pay cut last month, after which he fired his agent. He said that the reduction in salary “p—-d me the [expletive] off” but that his decision to retire had “nothing to do with that.”

Incognito arrived in the NFL in 2006 with a reputation as a hothead, having had so many acrimonious encounters with both opponents and teammates during a standout college career at Nebraska that he ended up leaving the school and transferring to Oregon for his senior season, only to be dismissed from that program before playing a game.

After being drafted by the Rams, Incognito racked up personal fouls and other ugly incidents, and he was released late in the 2009 season. He was picked up by the Bills and signed in the offseason with the Dolphins, with whom he gained his greatest notoriety, after details emerged of his abuse of another Miami offensive lineman, Jonathan Martin.

During that episode, which resulted in Incognito being suspended for the second half of the 2013 season and remaining a free agent until 2015, he was accused of racist remarks, and similar allegations occurred at other points in his career. Most recently, Jaguars defensive end Yannick Ngakoue claimed that Incognito hurled “some weak racist slurs” his way during a playoff game in January, although Bills General Manager Brandon Beane described that as “a misunderstanding” and the two players subsequently “hugged it out” after Incognito said he apologized at the Pro Bowl.

Of his anger over his pay cut, Incognito told the News on Tuesday, “There’s more to that story, there’s many layers, but I don’t want to get into that right now. I just want to go out with the proper tone and say, ‘Listen, enough’s enough. I’m done with football, I am retiring. My body is telling me it’s time.’ ”

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