Matt Kemp was "surprised and definitely disappointed" to learn the extent of the damage to his left shoulder after undergoing surgery earlier this month.

However, he expects to be ready to play by Opening Day 2013.

"I wish it just would have been a cleanup and taken six weeks," Kemp said. "They actually had to go repair some things. Now, I think it's going to be closer to January before I'm getting to hit and do a lot of other things."

He injured the shoulder banging into a wall in Colorado on Aug. 28. He batted .214 with 15 RBIs in 28 games after hurting his shoulder.