In fact, the 29-year-old is drawing comparisons to a former beloved Celtic: Isaiah Thomas.
"We had a little guy like that, similar to that on our team in Isaiah Thomas," Smart told The Athletic. "It's kind of funny some of those little guys that can score the ball, they have an energy and a motor about them you don't see very often."
It's a fair comparison to make. The 6-foot-1 Walker has seen his average points per game average increase nearly every season since he was selected by the Charlotte Bobcats in the first round of the 2011 NBA Draft. For two seasons, the 5-foot-9 Thomas was Boston's premier scoring threat.
But at this point in Walker's career, he's more than just a scorer. The UConn product has made it a point to improve on the defensive side of the ball, and Smart -- an NBA All-Defensive First Team member last year -- has taken notice.
"The dude can actually play defense," Smart told The Athletic. "Guys who score the ball can kinda get that notion that, you know, they're not really good defenders. Especially him being a little guy, it's probably harder to play against him because of a lower center of gravity. Plus, he's feisty. So he's really good, he's a really good defender and he plays both ends.
"You didn't get to really see that a lot from him because he exerted so much energy on the offensive end that he had to take a couple of breaks off on the defensive end, understandably."
Walker has been putting that energy on display this summer at the 2019 FIBA World Cup, most recently powering Team USA to a win over Brazil with a team-high 16 points.
Celtics fans can look forward to Walker donning the Green and White for the first time in the regular-season opener Oct. 23 vs. the 76ers.
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Marcus Smart compares Kemba Walker to ex-Celtics teammate Isaiah Thomas originally appeared on NBC Sports Boston