The Mavericks shot just 2-of-14 from the field as a group and managed only 11 points in the first quarter. Their last field goal came at the 4:35 mark when Cooper Flagg made a contested layup. While shutting them down, the Spurs surged ahead to grab a 21-11 lead at the end of the first quarter.

Cooper Flagg's summer league debut wasn't perfect. But there were flashes of greatness, and at this stage the Mavericks would be wise to let him fail.

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