McClellin recorded 20.5 sacks and 33 tackles for a loss during his four-year career with the Broncos.
Although McClellin lined up primarily at strong side linebacker at the Senior Bowl, Bears general manager Phil Emery said Thursday night the Bears will use McClellin at left defensive end.
"He showed us some natural pass-rushing ability the other defensive ends [still left on the board] did not," Emery said. "Shea is a high-level player. He's relentless with his motor."
The chance to join an organization with an illustrious history, such as the Bears, appealed to McClellin.
"I was definitely excited and happy to be part of a great organization," McClellin said in a conference call with Chicago media on Thursday night. "I really can't wait.
Emery was impressed by McCLellin's versatility.
"He's got really quick feet and hands as a pass-rusher," Emery said. "He has natural hips as a pass-rusher. In his normal starting role at Boise was as a middle linebacker, and he would come down and rush on third downs or in sub-package situations. There is a lot of versatility with this player.
Emery said the Bears sent defensive line coach Mike Phair to put McClellin through a private workout during the pre-draft process.
"I thought I might have a chance to go to Chicago and I just ended up there," McClellin said. "My private workout went great. I thought I did good and that the defensive line coach, coach Phair liked me. I thought they liked me and that I had a shot. They ended up picking me, which is great."
With a void opposite Peppers, the Bears will be counting on McClellin to deliver as a rookie. He says he's up for that challenge.
"I think I can (produce right away)," McClellin said. "That's why they picked me up. I think they believe in me and I think I'll get after the quarterback. I think I'll be able to make an impact."