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A time-tested sports mantra is that a playoff series doesn’t truly begin until one of the teams loses a home game, but the Celtics exposed the Nets in multiple ways in taking the first two games in Boston.

Celtics coach and former Nets assistant Ime Udoka coached circles around former boss Steve Nash with a brilliant swarming defensive game plan against Kevin Durant, who combined with Beantown villain Kyrie Irving for an 8-for-30 shooting night in a 114-107 loss in Game 2.

“Ime knows us really well,” Irving said. “I think he has some keys in the treasure chest that he’s telling those guys.”