AP Photo/Stephan Savoia

Chris Wilcox is eager to get back on the floor for the Celtics.WALTHAM, Mass. -- Chris Wilcox knows about patience at this point in his career.

But patience is far more bearable in some situations than it is in others. Consider Wilcox's rehabilitation from heart surgery to repair an enlarged aorta back in March. There was no choice but to be patient, as he worked his way back from square one. He had to regain his wind and his stamina, increase the strength in every part of his body, and rebuild his core muscles, which took perhaps the biggest hit from the procedure.

So to go through all of that, only to be sidelined for much of training camp by spasms in his lower back? In terms of injury severity, it's a mountain versus a molehill, which is why it's a little bit more difficult for Wilcox to remain patient this time around.

"I'm just six months out of surgery, so I got back out here, everything was feeling so good and I missed the game so much, I'm just out here playing off of adrenaline," Wilcox said after practice on Thursday. "My body just wasn't all the way healed.

"I missed the game so much I was just rushing into it, and like I said, things happen, and I think that just happened to slow me down and let me know, like, 'You did just have surgery,' so, like I said, I've just got to take it one day at a time and I've got to slow down."

Wilcox said he first started having trouble with his back on the second day of training camp, before the team even left for their weeklong trip to Europe. He sat out both games over there, and has remained on the sideline since the team returned. He said he's been doing anything he can to stay involved as the team continues to build on the opening days of training camp, even serving as a mock referee for some of the scrimmages.

"Well, they hold me out of a lot of stuff. They just want me to focus on my cardio and then just lifting weights and getting my core back strong, because that's what really broke down during the surgery process," Wilcox explained. "So, I'm just trying to get back in the swing of things. Every day they try to hold me out of everything, because, once I see it, and they're talking trash, you know, that's competitive, that's me, that's what I want, and it's just hard for me to sit and watch. But at the end of the day, I know what I've got to do for the long run."

The long run should be more important to Wilcox than to almost any other player. He's entering his 11th NBA campaign, and has yet to play in the postseason. The Celtics were a lock for the playoffs last season, and just as Wilcox was cementing his role in the rotation -- thus guaranteeing court time in the playoffs -- he was sidelined by his heart ailment.

Still, even the vision of finally partaking in the real games come next April and May has to be slightly hazy for Wilcox right now. It's not just the most basic desire to play that has him itching to get back on the floor, but the knowledge that his spot isn't exactly sitting there waiting for him. Having been a steady observer for the last week has made him aware of how productive the four-man rotation of Kevin Garnett, rookie Jared Sullinger, Brandon Bass and Darko Milicic has been.

Sullinger and Milicic were two of the more surprising standouts while the team was in Europe, and as the C's tinker with lineups, each of them could start alongside Garnett at some point this season.

Wilcox's return date is still up in the air, though he was back on the court getting up shots after practice Thursday. Head coach Doc Rivers said that Wilcox won't be returning soon, and Wilcox himself was hesitant to lay down a specific time frame.

"I leave that up to the trainers, and, now, like I said, they just want me to get in shape and get back healthy so I won't have to miss any more practices or game situations," Wilcox said. "So, I'm just trying to get my body right and get my confidence back up."

Whenever he does return, Wilcox's best bet is to come back with the same mindset that he possessed midway through last season. At times, his energy, all by itself, was his greatest weapon when he was on the court. There's still plenty of time to re-establish that role, as long as he can harness that same intensity. Right now, it's looking like that won't be a problem, as it's been difficult for him to keep that energy level in check on the sideline, the same way it's been difficult to stay patient throughout this latest setback.