West Coast ruckman Jonathan Giles has announced his retirement due to an ongoing issue with his knee.

Giles played nine games in his two seasons with the Eagles, and has played 63 games since making his debut with GWS in 2012.

The 29-year-old played 51 career games for the Giants, and added three matches with Essendon in his lone season at the Bombers in 2015.

Giles had struggled with a knee injury in recent years, and told the club's website that doctors had told him it wasn't going to get better.

“The knee was no good; the osteoarthritis from several years of bone-on-bone has got the better of it,” Giles told westcoasteagles.com.au.

“I step away from AFL footy knowing that I gave everything I had, left no stone unturned and scrapped for every opportunity possible.

“I’d sincerely like to thank the club for the opportunity to continue my dream of an AFL career and I wish my teammates and the club every success moving forward.”

West Coast's general manager of football Craig Vozzo thanked Giles for his time with the club and wished him well for the future.

“Unfortunately for big Joffa the knee injury has impeded him, particularly this season,” Vozzo told the club's website.

“In light of the medical report, he really had no option but to retire from AFL football.

“He played an important and selfless role for the club, coming here with no promises to offer us coverage in the ruck area.

“We wish to think Joffa for his efforts on and off field in the last two years and wish him every success with the next phase of his life.”