Anthony Davis and James Harden also withdrew from Team USA consideration in July.
Pelicans rookie Zion Williamson will not join Team USA at the FIBA World Cup in September, according to The Athletic's Shams Charania.
Williamson's decision followed a pair of defections from Team USA on Monday. Wizards guard Bradley Beal and Sixers forward Tobias Harris are also opting out of Team USA training camp and the FIBA World Cup.
Bulls forward Thaddeus Young and Celtics guard Marcus Smart earned invitations to the Team USA training camp on Monday, per Charania.
Monday's trio joins a slate of NBA stars to skip FIBA training camp and the subsequent tournament. Anthony Davis and James Harden will both skip the festivities as they prepare for the 2019-20 season.
There are 17 players on the current FIBA training camp roster, headlined by Damian Lillard and Kemba Walker. The final roster will consist of 12 players.
FIBA World Cup play begins on August 31.