L.A. Clippers guard Patrick Beverley's ball chuckin' celebration after beating the Lakers is gonna cost him a piece of that new contract he just signed ... 'cause the NBA just fined him $25k for the toss.
Beverley had possession of the ball with the clock winding down in the Clips' 112-102 win over the Lakers on Tuesday ... and instead of handing the ball to the ref next to him, Bev threw it into the stands.
Kiki VanDeWeghe -- EVP of Basketball Operations at the Association -- announced the hefty punishment on Wednesday ... saying Beverley was fined "for throwing the game ball into the spectator stands.