Victor Wembanyama came alive in the fourth quarter of his first game. Unfortunately for the Spurs, so did Luka Doncic.
Wembanyama and the San Antonio Spurs led 117-115 with 2:34 left to play, but the Dallas Mavericks closed the game on an 11-2 run, thanks to their All-Star guards.
Doncic had a three-point play and the stepback dagger three that clinched it, part of his 33-point…