PITTSBURGH (AP) -- James Harrison spent a decade as one of the NFL's most feared players.
What the five-time Pro Bowl linebacker fears now, however, is missing out on the childhood of his two young sons.
Harrison announced his retirement on Saturday, saying the urge to squeeze in one more season no longer competes with the need to stay at home.
''My love for the game isn't strong enough to make up for missing one more birthday or first day of school,'' Harrison posted on his Facebook page. ''I am retiring as a man who is truly grateful for all of his blessings.''
The 36-year-old was a free agent after spending the 2013 season with the Cincinnati Bengals. He visited the Arizona Cardinals earlier in the week but did not sign a contract. He called the decision ''a difficult one'' but insisted he has no regrets.
''My love for my family and the need to be there for them outweighs my desire to play the game,'' he wrote.
Harrison built a reputation as one of the NFL's toughest and most intimidating players during 11 seasons with the Pittsburgh Steelers, where he worked from undrafted free agent to the 2008 NFL Defensive Player of the Year.
His 100-yard interception return for a touchdown to end the first half of the 2009 Super Bowl against the Arizona Cardinals is one of the most electric plays in league history and showcased the relentlessness that made him respected in the locker room and a polarizing figure in the league office.
A seemingly perfect fit for defensive coordinator Dick LeBeau's 3-4 defense, Harrison finished with 66 career sacks, including 16 in 2008 when he helped guide the Steelers to their sixth championship.
As the years wore on, however, the injuries - and the fines from NFL commissioner Roger Goodell - piled up. He parted ways with the Steelers in March, 2013 when he declined to take a pay cut. He landed in Cincinnati, where he had two sacks and an interception in a diminished role. The Bengals cut him in March and while he continued to work out hoping the phone would ring, he couldn't find the proper landing spot.
In many ways Harrison's success was emblematic of ''The Steeler Way.'' Signed as training camp fodder in 2002, Harrison spent two years on the practice squad before getting signed by the Baltimore Ravens, who sent the undersized Harrison - listed at 6-feet - to NFL Europe for some seasoning. The Ravens eventually cut him loose and Pittsburgh brought him back hoping he had matured.
It ended up being one of the better bargains in team history. From 2007-11 Harrison was one of the best outside linebackers, a stretch when the Steelers finished in the top five in fewest yards allowed each year and made it to the Super Bowl twice.
Yet Harrison's violent play sometimes came at a hefty price. He was fined multiple times for hits to the head.
Feeling he was being unfairly persecuted by the league, Harrison called Goodell a ''crook'' and a ''devil'' during an interview with Men's Journal in early 2011. Harrison later apologized and promised to clean up his act.
It didn't exactly work. Harrison was suspended for a game in December, 2011 after his helmet smacked into Cleveland quarterback Colt McCoy's facemask a moment after McCoy released the ball.
Harrison did not receive any letters from the commissioner's office in 2012, but his physical style of play took a toll on his body. He missed all of training camp with a knee injury and admitted he had endured ''a dozen'' concussions over the course of his career.
Rather than risk another one, he's staying home for good.
AP NFL website: www.pro32.ap.org and www.twitter.com/AP-NFL