Broncos tight end Jake Butt will undergo clean-up surgery on his left knee after another setback in recovery from a third career ACL tear, a source confirmed.
The source said no repair work will be done on the knee.
Butt suffered the injury during practice last September and had slowly worked back into a full participant through the course of training camp. Butt made several attempts over the last year to play, including 11 snaps and two catches in his preseason debut last week, with each comeback followed by a complication.