Cooper Flagg strolled into UNLV’s Thomas and Mack Center at 4:17 p.m. for his Summer League debut, wearing Dallas Mavericks gear, bright white New Balance shoes, and an emotionless look on his face as he passed through security.

Flagg's first points as a pro came on a slam dunk with less than five minutes to go in the first quarter. The Mavericks guard finished with 10 points, six rebounds and eight assists in his debut. He played 32 minutes, making 5 of 21 field goals, missing all five of his three-point attempts.