Danny Ainge: Celtics guard Marcus Smart resumes basketball activities

Boston Celtics point guard Marcus Smart resumed on-court basketball activities this week and is trending toward a return later this month or in early January, according to Celtics president of basketball operations Danny Ainge.

"Marcus had a really good day [Wednesday]," Ainge told the "Toucher and Rich" program during his weekly call to Boston sports radio 98.5 The Sports Hub. "He got out on the court for the first time and he’s running around and felt good. Barring any setbacks, I think it’s probably looking closer to the end of this month or the beginning of the new year. He looks good, and we’re excited to get him back soon. But I’m not sure exactly when that is. That’s sort of a day-to-day thing, but I’m looking at it more at the end of this month."

Smart has been sidelined since Nov. 20 after suffering a subluxation of the proximal tibfib joint when he banged knees with Brooklyn's Thomas Robinson while trying to defend a layup attempt. Smart has missed Boston's last 14 games -- a stretch during which the Celtics are 7-7 -- and would stand to miss at least six more if he's not able to return until the new calendar year.

The Celtics have maintained a high level of defensive play without Smart, but Boston's defensive rating over that 14-game span is 100.2, ranking 11th in the NBA in that span. For the season, Boston is tied for fourth in the NBA with a rating of 97.8.

"Our defense has been good, it’s been pretty good all year, with the exception of maybe right out of the gates, but I think that Marcus just gives us the depth," Ainge said. "You can always get by without any one of your players for a little bit of a time, but it does catch up. Isaiah [Thomas'] and Avery [Bradley's] minutes have increased in Marcus’ absence. Both have had great years, but we need Marcus. We need Marcus’ defense and we need his versatility."

Smart missed 15 games his rookie season and has now missed a total of 17 games this season due to injuries. Some have wondered if Smart is injury prone, but Ainge has maintained that, despite a growing collection of maladies, most have been fluky.

"I think he throws his body out there and he plays basketball like a linebacker, but time will tell on [whether Smart is injury prone]," Ainge said. "Because he hasn’t had any serious injuries or needed surgery, so that’s helpful. ... I hope he's not injury prone."

The Celtics selected Smart with the No. 6 pick in the 2014 NBA draft. He has averaged 9.8 points, 3.8 rebounds, 3.2 assists and 1.8 steals per game in nine appearances this season. Smart is an All-Defense-caliber player whose size allows coach Brad Stevens to play with defensive matchups.

With Boston's first-unit offense thriving in Smart's absence as Thomas has elevated to a starting role alongside Bradley, Stevens has said Smart is likely to return in a reserve role and on a minutes restriction as he shakes off the rust.

Smart will help a second unit that's played excellent defense throughout the season. The longer-range question is whether he'll re-elevate to a starting role. The Celtics have had great success bringing Thomas off the bench since his arrival last February, and Boston's reserve groups have struggled to generate consistent offense without him. Smart is shooting just 36.2 percent for his career and must continue to develop his offensive abilities, particularly when handling the ball at the point guard spot.