Rehab is driving Marcus Smart ‘crazy,’ but he’s working on it

Marcus Smart last played March 11 when he damaged his right thumb diving for a ball.file/Michael Dwyer/associated press

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PHOENIX — It’s early on Monday evening and the Celtics in the locker room are preparing for their game against the Suns that is just over one hour away. Some sit at their stalls with headphones on and nod to whatever beat is thumping. Some are on the floor being stretched by the team’s training staff. Most players already have their uniforms on, and those who do not are grabbing them.

But Marcus Smart is not a part of this rhythm. He is sitting in a swivel chair with a splint covering his surgically repaired right thumb and picking at a plate of fruit with his left hand.

Every minute or so, he peeks up at the large television showing footage of a recent Suns game, but there’s really no benefit to scouting this opponent, not tonight at least.

“It drives me insane,” Smart said in an interview with the Globe. “You get to the gym, walk in, and really that’s it. I don’t put on a jersey and don’t do any of that. That’s what I’ve been doing my whole life, so it does drive me a little crazy. But it’s a bigger picture, and my time is going to come.”

When the Celtics played the Pacers on March 11, there was a loose ball on the floor, and that usually means that Smart will soon be on the floor, too. He sprawled and swiped and tore a ligament in his right thumb in the process.

Smart underwent surgery March 16, and the Celtics said he would be sidelined for 6-8 weeks. He is optimistic that he will be able to return for the Eastern Conference semifinals, if the team makes it that far.

“Definitely right now, that’s what we’re shooting for,” the 24-year-old guard said. “The way it’s going now, we’re on the right path. Hopefully nothing happens where it gets delayed.”

The Celtics are considerably undermanned. Gordon Hayward has continued his recovery from October’s gruesome ankle injury, Kyrie Irving is expected to miss 3-6 weeks after undergoing knee surgery Friday, and Daniel Theis is out for the year with a torn meniscus.

All three players have been going through rehabilitation away from the team. But Smart, the only one who did not suffer a leg injury, has been on this eight-day road trip with the team. It has been good for him to be around his teammates, but it has also been difficult for him to sit and watch games unfold right in front of him. The sport is almost taunting him.

“We’re trying to get him as engaged as possible,” Celtics coach Brad Stevens said. “He’s in every film session, he’s at every practice, and he’s at every game. But it’s hard when you’re unable to play the game. That’s a hard thing to handle emotionally, because he is a competitor.”

Smart is encouraged by his progress, even if it has come slowly. His cast has been replaced by a smaller, less-intrusive splint that he is able to take off for things like showering. There is an open hole at the top of the splint that allows thumb movement.

Smart said he has been able to do some light thumb exercises, and when he is asked what that includes, he smiles and wiggles his thumb slightly.

“I try to play the game a little bit with it,” he said. “You know, that’s the movement you do when you play video games. But we’re heading down the right track. I have a little more movement than I did a few days ago, so that’s good.”

Initially, pain medications were making it difficult for Smart to complete cardiovascular exercises. But the dosages have been decreased, and now the pain mostly comes at night. On Monday, Smart completed a vigorous one-hour workout focused on lower-body and abdominal exercises. He said he hopes to begin some light basketball exercises using his left hand next week.

For now, he is seeing basketball through a different lens. He is consuming more film and watching games with a coach’s eye from the bench. He said it’s been a joy to witness the way these young Celtics have responded to adversity recently. He just wishes he could help.

Smart was injured doing what he generally does best: being a relentless competitor who will dive or jump for anything, a player who is just as comfortable when he is landing on the floor as he is when he is running on it. But when he returns, he insists, he will be the same Marcus Smart.

“This injury is not going to change me at all,” he said. “All that stuff, that’s what makes me who I am. That’s what separates me from other guys. I’m not going to change that for the world. Things like this happen. You deal with it how you need to, and pray and hope it’s nothing that can’t be fixed, and then you keep going. I’m going to keep going.”