Arizona football’s defensive line is getting a tad bit smaller as of Friday, when 6-foot-2, 313-pound defensive lineman Sharif Williams retired from football.

Williams posted on both his Instagram and Twitter accounts Friday afternoon to announce his retirement due to a knee injury he suffered in high school.

“Dear family and friends, I have made the decision to (medically retire) from playing football,” Sharif wrote on Instagram. “This is one of the hardest decisions I have ever made in my life.”

Williams was a three-star recruit in the class of 2013 and redshirted his freshman season.

“I have been battling every day knee pain from my high school injury,” Williams said. “This maybe a big surprise to most because I’ve been acting like I was perfectly fine just so people wouldn’t worry about me … but I’ve been going through a lot. I’m finally at the point where I can say I gave it my all and I’ve done more then most people who have had an injury like mine.”

This could be a very significant loss for the Wildcat defensive line for a few years to come. Williams brought in a physical presence that is not seen as often in the system.

“I’ve always wondered who would I be if I wasn’t Sharif the football player,” Williams said. “It’s time for me to find out.”

Williams attended the same high school as Nick Wilson and Devon Brewer, both teammates at Arizona. Coming out of high school, Williams was recruited by Houston, Oklahoma, Oregon State, San Jose State and Utah.

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