But though he admitted he "could barely walk," Berkman sounded upbeat Wednesday at Osceola County Stadium, saying he feels "pretty good" considering the circumstances.
"I feel pretty good," he said at the home clubhouse at Osceola County Stadium on Wednesday, adding that he "could barely walk."
The 34-year-old first baseman believes it's "still within the realm of possibility" that he can be ready by Opening Day, which for the Astros is April 5 against the Giants. But before he can progress from simple leg raises and quad-tightening exercises, Berkman is waiting for the swelling in his knee to go down, and he estimated it's about 10 days post-surgery before that happens.
As for how much game action Berkman will need before he's ready to step into a regular-season contest?
"We're going to have to see," Manager Brad Mills said. "I can't sit here and say he's going to need three games, four games, a week. You can't say that, because you don't know exactly how he's going to feel, how he's going to heal and how the knee is going to be going. So we're going to just have to wait and see with how it goes and make sure he's 100 percent, both physically and baseball-wise, if he's ready to play."
The good news is that if Berkman has to be placed on the disabled list at the start of the season, it doesn't automatically mean he'll miss at least 15 days. Major League Baseball's earliest retroactive date is March 26 this year, meaning Berkman would be eligible to return as early as April 10 -- a date that would put him out for the first four games.
After feeling soreness in his left knee throughout the early part of spring, Berkman opted for arthroscopic surgery to remove loose cartilage on Saturday, with the initial prognosis saying he'd be out 2-4 weeks. If he's not ready for the start of the season, Geoff Blum is likely to be the club's starting first baseman.
But Berkman is still focusing on being ready for Opening Day, which is less than three weeks (19 days) away and counting.
"I would run out there without having played any games," Berkman said. "But to be effective, obviously, it takes a little bit to get your timing back and get up to speed. Heck, if I felt like I was ready to go and I hadn't played any games, that wouldn't keep me from going out there on Opening Day."
Alden Gonzalez is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.