James Wilks has retired from the sport © UFC Enlarge

TUF 9 winner James Wilks has announced his retirement from the sport.

The English welterweight, who earned a contract with the UFC after beating DaMarques Johnson in the final of 'The Ultimate Fighter: UK vs. USA', has been forced to end his career due to injury. He has not fought for 18 months.

"A few of you have been asking when my next fight is," Wilks said on Twitter. "Unfortunately, I have had to retire due to injury. Now coaching at Lightning MMA."

Wilks retires with a record of seven wins and four losses in MMA, including one win and two defeats in the UFC. His most recent fight saw him lose to Claude Patrick at UFC 120 in October 2010.

He will now concentrate on working as a coach with Lightning MMA, the California-based gym.

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