The NBA fined several players $15,000 each for participating in an unsanctioned University of Washington alumni basketball game, league sources told Yahoo! Sports.

The NBA fined Philadelphia 76ers forward Spencer Hawes, Memphis Grizzlies guards Quincy Pondexter and Tony Wroten and Sacramento Kings guard Isaiah Thomas for participating in a June 23 game at Alaska Airlines Arena in Seattle, league sources told Y! Sports.

It wasn't immediately known if several other former Washington Huskies involved in the game, including Chicago Bulls free-agent guard Nate Robinson and Toronto Raptors guard Terrence Ross, were subject to the fines.

Washington coach Lorenzo Romar organized the game. The NBA's collective bargaining agreement mandates that players can't play in public offseason games prior to July 1 or after Sept. 15 without league approval.

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