Barring a medical miracle, Jason Hunter is not likely to play in 2012.

The Broncos’ starting defensive end suffered a torn right triceps during an early training camp drill Tuesday.

Hunter underwent surgery Wednesday and likely will miss four months, putting his return to sometime in December. Still, it is expected that Hunter will land on Denver’s season-ending injured reserve list.

“They said it was like 95 percent torn,” Hunter said Wednesday afternoon. “They told me mine was hanging on like a piece of rope. I don’t want to count myself completely out even though I know the severity of my injury. But I’m going to let the team coach me up on this and wait until they tell me what the next step is.”

Hunter said he felt something wrong while doing a shuffle-and-strike individual drill in the early part of practice Tuesday. As he lined up in the three-point stance, his arm felt extremely weak. When the team moved over to a sled for another strike drill, he couldn’t extend his right arm.

“I felt something wrong, but I never had this before so I told myself, ‘I’m a football player, I can fight through this.’ So I just kept practicing,” Hunter said. “It felt weak, but I got it wrapped up and kept practicing, but towards the end it got to the point where I couldn’t lift my right arm. I finally told the coach: I’ve got to sit this last period out.”

Besides Hunter, the Broncos lost starting right guard Chris Kuper to a broken left forearm Tuesday.

Kuper also underwent surgery Wednesday and is expected to be out six weeks, which would mean missing the first three games of the season.

“I saw him leave the drill, but I didn’t know anything was wrong until I went into the trainer’s room and he was sitting there with his arm bandaged up,” Hunter said of Kuper.

Hunter, who is two weeks shy of 29, has been a productive player for the Broncos, starting a combined 14 games the past two seasons. He had been the team’s No. 2 defensive end during the offseason, but his spirited, almost maniacal play early in camp caused defensive coordinator Jack Del Rio to move Hunter ahead of Robert Ayers in the team’s 4-3 base defense two weeks ago.

Hunter often was involved in altercations with members of the Broncos’ offensive line during 11-on-11 drills.

“I was just trying to go as hard as I can,” Hunter said. “I’m sorry I can’t be out there with my teammates, my great coaches, coach (Jay) Rodgers and Jack Del Rio. I loved working with those guys. It was a great atmosphere. This is tough.”

Broncos defensive tackle Ty Warren suffered a similar injury at about the same time last year. After initially holding out hope of returning for the final six weeks of the season, Warren opted to have season-ending surgery.

The Broncos are expected to replace Hunter with either Ayers or second-round draft pick Derek Wolfe in the base defense.

Mike Klis: 303-954-1055, mklis@denverpost.com or twitter.com/mikeklis