Denver Broncos left tackle Ryan Clady has torn his left ACL during practice, and is likely to miss the 2015 season.
Clady was injured while blocking on a pass play during a drill, and after being treated by trainers he didn't participate for the rest of the session.
"We really weren't that worried last night, everybody felt good, but we felt like we'd take a look at it this morning, and unfortunately we got some horrible news," coach Gary Kubiak told the media.
"Just devastating, just feel bad for Ryan."
This latest setback will be the fourth major surgery in the last five years for Clady, with the others coming on his left knee, shoulder and foot.