It was quite a story for James Harrison, who went from undrafted to winning a pair of Super Bowl Championships and one Defensive Player of the Year award, but the NFL journey has come to an end.

On Monday, the 39-year-old took to Instagram and announced his retirement, all while thanking the coaches for the support:

Harrison was cut by the Pittsburgh Steelers and joined the New England Patriots late in the 2017 season, registering two sacks in his Foxborough debut. Harrison also helped the Patriots reach Super Bowl 52, where they lost 41-33 to the Philadelphia Eagles.

Of course, the bulk of Harrison's career was with the Steelers - and that's where virtually all of his big moments came from. Signed as an undrafted free agent out of Kent State in 2002, Harrison didn't need long to fully develop as one of the game's toughest defensive players.

Harrison helped the Steelers form the NFL's best defense throughout the 2000s - and for much of the 2010s. He helped the Steelers win Super Bowls 40 and 43, and will be best remembered for this iconic play:

Harrison was also named Defensive Player of the Year in 2008, finishing with 101 tackles, 16 sacks, seven forced fumbles and three passes defensed. He was also named to five Pro Bowls during his illustrious career.

Besides his play on the field, Harrison was also known for some of his controversial statements off the field. After Pittsburgh won Super Bowl 43, Harrison (along with his teammates), opted not to visit the White House. Harrison also didn't visit President George W. Bush when the team won Super Bowl 40 three years earlier.

In 2011, Harrison also did an article on Men's Journal, with the cover photo of him wielding two guns. Harrison called commissioner Roger Goodell "a crook and a puppet," and voiced how much he hated him.

Harrison was one of the more polarizing players of his era, but the controversial yet successful career comes to an end today. Perhaps a spot in the Pro Football Hall of Fame is the next stop.

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