The Celtics intentionally fouled Andre Drummond while up 32 points and the Bulls weren’t happy

Billy Donovan approached Joe Mazzulla during the fourth quarter of the NBA’s In-Season Tournament.

The NBA used point differential during group play as a tie-breaker to advance to the knockout phase of the In-Season Tournament.

That means even though Celtics head coach Joe Mazzulla said before the game that point differential would have “zero” impact on how he would coach his team against the Bulls on Tuesday night, he changed his tune when the game actually started.

After the Nets defeated the Raptors during the seeding games, however, Boston needed to defeat Chicago by at least 23 points in order to advance to the quarterfinals.

So with more than seven minutes remaining in the game, Mazzulla instructed his team to intentionally foul Bulls big man Andre Drummond to send him to the free-throw line.

Bulls head coach Billy Donovan was visibly upset by the decision and approached Mazzulla on the sidelines.

With a referee nearby in case matters got any more tense, Mazzulla explained why he chose a route that was somewhat embarrassing to Drummond.

After the game, meanwhile, the two coaches elaborated on their feelings about what happened and what was said during their exchange.

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