Stanford inside linebacker Sean Barton, who was second on the team in tackles last season, is retiring from football with a year of eligibility left.

“I’ve loved football for as long as I can remember,” he said on Instagram. “I still love it. But now it’s time to hang up the cleats and focus on some things that are bigger than sports. I’m incredibly grateful for my family, my teammates, my coaches and the opportunity I got to come here. It’s an honor to be a Stanford Man.”

He did not respond to interview requests.

The 6-foot-3, 224-pound redshirt junior took part in 92 tackles, trailing only inside linebacker Bobby Okereke’s 96.

Barton came back strong from a major knee injury that ended his 2017 season in the third week at San Diego State.

He finished his career with a team-high eight tackles, including five solos, in the Sun Bowl victory over Pittsburgh.

A native of North Salt Lake, Utah, Barton signed with Stanford in 2013, then served a two-year LDS church mission in the West African nation of Benin.

His departure and the graduation of Okereke, Mustafa Branch, Jordan Perez and Ryan Beecher leave the Cardinal without much experience at inside backer.

Junior Andrew Pryts, a converted safety, and freshmen Jacob Mangum-Farrar and Ricky Miezan are the only holdovers at the position.

Stanford did not sign an inside linebacker in its incoming class. It’s possible an outside backer could be moved inside.

Tom FitzGerald is a San Francisco Chronicle staff writer. Email: tfitzgerald@sfchronicle.com Twitter: @tomgfitzgerald