Bergesen reportedly sustained the injury while shooting a TV commercial for the team in early December.
He's been participating in the team's throwing program at the Orioles' Spring Training home in Sarasota, Fla., but has been unable to throw off a mound since the shoot more than two months ago.
"I think initially I will probably be 10 days behind everyone, but I am not coming off a major arm injury or surgery," Bergesen told the Sun. "Once they feel I am capable of being on the mound and having good sessions, then I will be caught up to everyone."
Bergesen, 24, got off to a strong start for the team in 2009, going 7-5 with a 3.43 ERA in 19 starts before taking a line drive to the shin on July 30 and being shut down for the rest of the season.
If healthy, he is expected to be in the starting rotation to open 2010.
The Orioles expect Bergesen to be ready to go by Opening Day, but team president Andy MacPhail told the Sun that they may monitor off-field events that require this kind of activity more closely down the line.
"We have already made some adjustments in terms of making sure we have medical personnel or baseball personnel present for anything we do in the future," MacPhail said.
The commercial shoot, filmed in an indoor batting cage at Camden Yards, was actually the first time he had thrown off a mound since sustaining the leg injury.
"Obviously, I hadn't picked up a ball -- I'm kicking myself in the head about it," Bergesen told the newspaper. "That's really what it was from -- not working on a mound up to that point.
"I just jumped up on the mound and gave it a go. I was trying to be game-speed. I was trying to be as realistic as possible with it. The production company that came in wanted it to be as realistic as possible. And I was trying to please, and I got caught up in a moment."
Lisa Winston is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.