WALTHAM – Celtics coach Doc Rivers said Wednesday he has been fined $25,000 by the NBA for suggesting that center Kendrick Perkins has been targeted by officials for setting illegal screens.

Rivers made the comments on Monday, one day after the Celtics lost 121-118 in double overtime to the Bulls in Chicago.

The team is leaving this afternoon for Chicago following a brief film session at their Waltham training facility. Game 6 is Thursday night in Chicago, with the Celtics leading the best-of-seven series, 3-2. A win sends them into the second round to face either Orlando or Philadelphia.