12:27 PM ET
BOSTON -- Celtics guard Marcus Smart said his mother, Camellia, began chemotherapy treatments Monday as she continues her fight after a recent diagnosis of bone marrow cancer, but she has implored her son to remain focused on Boston's playoff run.
The Celtics are 7-2 since Smart returned from thumb surgery late in Boston's first-round win over the Milwaukee Bucks. On Sunday, Smart's mother was surrounded by family as she watched Boston's Game 1 triumph over the Cleveland Cavaliers in the Eastern Conference finals on Mother's Day.
"It's tough. I'm not going to lie, it is tough," Smart said. "I'm professional; we have a job to do. And that's something about my mom, she's real big on, 'I'm going to be OK, go handle what you gotta do. And I'm going to be all right.' That gives me a little comfort to go out there and not really feel guilty of being here instead of there with her.
"But it is tough. It's tough, but I have a great support [system] around me."
Smart said he already had one missed call from his mother by the time he returned to his locker stall after Sunday's lopsided win. He called his mother back to screams of joy.
"My whole family was actually watching. They all went over the house," Smart said. "It was good to hear everybody. When she called me, the smile and joy that she had in her voice lit up my day."
Of course, Smart's mother also had some advice: She wanted her son not to hesitate when he has open looks.
"My biggest critic and my biggest fan, and I love her," said Smart.
Smart said his mother will undergo chemo treatments three times a week. "She's doing well," he said. "She's responding."
With Smart on the court this postseason, the Celtics own a defensive rating of 100.8, or 3.5 points better than Boston's postseason average. Smart's return might have been key in the Celtics outlasting the Bucks in seven games in Round 1, and he was elevated to a starting role for part of Boston's second-round series victory over the Philadelphia 76ers.
Smart has struggled with his shot while working back from thumb surgery, but he's averaging 10.4 points per game on 34.1 percent shooting. He's added 4.6 assists, 3.9 rebounds, and 1.7 steals over 30.4 minutes per game.
Smart isn't just dealing with the thumb issue, he further battered his right hand diving on the court early into his playoff return, and it's caused lingering soreness throughout the hand.
But it's not anything that will keep him off the court, not when his mother is so adamant that he be out there.
"This hand of mine," Smart said looking down at his injured paw. "Especially this right one's been through tremendous ups and downs, man. Still fighting. I'm just trying to hang in there. I can rest after the season."