"He's got a little swelling, not believed to be serious," coach Rick Carlisle said after the 93-88 loss that dropped Dallas to 0-2. "It doesn't make any sense to rush through the weekend and try to play tomorrow."
Smith tore the anterior cruciate ligament in his left knee in August 2015, the summer before his senior year of high school. He experienced swelling in the knee after a shootaround Friday -- Carlisle said that has been an issue in recent weeks -- and the decision was made to not start him less than an hour before the game.
"He's had a little bit of minor swelling throughout training camp," Carlisle said. "It's just one of the symptoms of having an ACL [surgery in the past]. Doc checked him out, and we think he's going to be fine."
Smith, 19, the No. 9 pick in the draft who has inspired optimism in Dallas that he can be the franchise's next cornerstone player, had 16 points and 10 assists in the season opener to become the youngest player in NBA history to record a points-assists double-double in his debut.