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.

The opening day of the NBA Las Vegas Summer League provided fireworks and the debut of No. 1 overall pick Cooper Flagg, who struggled to find his shot in a dramatic win over the L

Cooper Flagg went 5-21 in his Summer League debut, but Jason McIntyre says it’s time to relax and let him develop.