Darren Sproles and the Philadelphia Eagles took to social media on Saturday to announce the NFL retirement of the former Kansas State Wildcats and Olathe North High School star.

Sproles posted a farewell to his playing days on the Eagles' website, with tributes to his NFL team, former Olathe North coach Gene Weir, his father, Larry, and late mother, Annette, among others.

"I owe so much to the game of football and I gave it all I had in return," Sproles wrote.

Sproles has appeared in six games this season and was placed on injured reserved last month following a torn right hip flexor. He was in his 15th NFL season, starting his career with the Chargers and also playing for the Saints before joining the Eagles in 2014. Sproles played 14 years. He missed his second season, in 2006, because of a broken ankle.

Sproles stands fifth on the NFL career-all purpose yards list with 19,696. An undersized running back — he's listed at 5-foot-6, 190 pounds — Sproles often heard he was too small for major college or the NFL, and he used the slights as motivation.

"I'm proud that I was able to prove my doubters wrong," Sproles said in his retirement announcement. "They told me that I wouldn't make it past a year in the NFL. Fifteen years later, I'm fifth all time in NFL history in career all-purpose yards. Look at the names who are above me on that list: Jerry Rice, Brian Mitchell, Walter Payton, Emmitt Smith.

"To be part of such an outstanding group is an incredible honor. But it also goes to show that no matter what people say about you, you can still achieve great things if you believe in yourself and put in the work."

Sproles was a football and track star at Olathe North, where he won the Simone Award as the Kansas City metro area's top football player.

At Kansas State, Sproles became the school's rushing leader with 4,979 yards, while rushing for 45 touchdowns. In the Wildcats' 2003 Big 12 championship season, Sproles set a school record with 1,986 rushing yards and finished fifth in the Heisman Trophy voting.

He rushed for 235 yards and added 88 receiving yards in the Wildcats' Big 12 title game victory over top-ranked Oklahoma at Arrowhead Stadium.

Sproles was taken in the fourth round of the 2005 NFL Draft by the Chargers and was chosen as the kick returner on the franchise's 50th anniversary team.

He joined the Saints as a free agent in 2011 and that year set the NFL record for all-purpose yards in a season with 2,696.

Sproles was traded to the Eagles for the 2014 season and made the Pro Bowl in each of his first three seasons in Philadelphia. His final three years have been shortened by injury.

His Pro Football Hall of Fame candidacy will generate plenty of discussion once he becomes eligible. Three of the players ahead of him on the career all-purpose list — Rice, Payton and Smith — and the one immediately behind Sproles, Tim Brown, are in the Hall of Fame.