Arizona offensive lineman Zach Hemmila died in his sleep Sunday night, the school's athletic director, Greg Byrne, announced on Monday.
Byrne said Hemmila "passed away in his sleep last night. We were notified this morning."
"We lost a great young man, and everybody in our program is hurting," coach Rich Rodriguez told reporters, per SB Nation.
Rodriguez said he didn't know any of the details about Hemmila's death.
Hemmila, 22, was from Chandler, Ariz. He was competing to start at center for the Wildcats.
He was a fifth-year senior and started six games last season for Arizona.
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