The Hawks dropped their Las Vegas Summer League finale with a 101-80 defeat to the Mavericks on Sunday night.
The Hawks finished the tournament with a 3-2 record.
First-round draft pick Kobe Bufkin led the Hawks with 18 points. Tyson Etienne added 14 points and Brady Manek added 11 points.
The Mavericks broke open a close game in the second half, outscoring the Hawks 36-18 in the third quarter. They led by as many as 28 points in the final two quarters. Jordan Walker had 22 points and Brandon Randolph had 20 points for the Mavericks, which ended with a 4-1 record.