"He was appreciative of the opportunity and hopes to be part of USAB again in future," agent George Langberg told Wojnarowski of Shamet's decision.
The 22-year-old guard was among those vying for a spot on Team USA's roster for the 2019 FIBA World Cup, which will be held in China from Aug. 31 to Sept. 15.
A number of players had previously withdrawn from consideration. Per the Associated Press, the list of players to have dropped out of the running include: Los Angeles Lakers forward Anthony Davis, Houstons guards James Harden and Eric Gordon, Portland Trail Blazers guards Damian Lillard and C.J. McCollum, Washington Wizards guard Bradley Beal, Cleveland Cavaliers forward Kevin Love, Detroit Pistons center Andre Drummond, Philadelphia 76ers forward Tobias Harris, Denver Nuggets forward Paul Millsap and Clippers center Montrezl Harrell.
No. 1 overall pick Zion Williamson also withdrew after being included on the Select Team.
USA Basketball men's national team managing director Jerry Colangelo previously discussed the importance of the Select Team, per Gina Mizell of The Athletic:
"The purpose of the Select Team is to help prepare our national team for the World Cup and to offer an opportunity for some younger NBA standouts to be involved in the USA Basketball national team program.
"... Not only will this group help prepare the United States for the FIBA World Cup, but it will also provide them with valuable experience at the USA Basketball national team level."
For Shamet, playing for Team USA would have provided him the opportunity to gain international experience while playing with some of the best players in the world. However, the Clippers' offseason acquisitions of two-time Finals MVP Kawhi Leonard and 2018-19 NBA MVP finalist Paul George have brought championship expectations to L.A.
Taken 26th overall in last year's draft, Shamet started his career with the Philadelphia 76ers before being traded to Los Angeles in a deadline deal. He averaged 10.9 points on 41.4 percent shooting in 25 appearances for the Clippers last season. He shot 42.2 percent from three-point range between Philadelphia and L.A.