Casey is recovering from a fractured transverse process in his lower back. The transverse process is where the muscles attach to the vertebrae.
He suffered the injury on April 14 while stretching to catch a throw from Pittsburgh second baseman Jose Castillo. As John Mabry of the Chicago Cubs was running out an infield single in the third inning, he stumbled crossing the bag and clipped Casey with his hip or left elbow.
Casey has already begun a rehab process that's included swimming, lifting [weights] and riding a stationary bike.
"Even being able to sit on the bike today was great," said Casey. "No pain. I feel like I'm ahead of schedule. I really do. I'm just itching to get back. ... It's been cabin fever being at home all this time."
He is cautiously optimistic about coming back sooner than expected, but doesn't want to push it because he doesn't want to aggravate the injury.
Casey was originally slated to miss six to eight weeks.
"I feel great," Casey said. "A couple of days ago, I started doing some things around the house. Basic movements, like bending over, I couldn't do for the first 10 days. That's why I'm optimistic about the whole thing. The way I feel right now, I just want to get back on the field."
That, of course, won't happen for at least a month. There's no rigid timetable for Casey resuming baseball-related activities, and he'll have to do a rehab assignment at Triple A Indianapolis when he's ready.
This isn't what Casey envisioned when he was traded to his hometown team during the off-season.
"I want to be out there contributing for this team and this city," Casey said. "Things like this happen sometimes. Injuries are part of the business. That's how it goes."