CLEVELAND—Halfway through Friday night’s Game 4, it seemed as if the Cavaliers were well on their way to tying this NBA Finals series at two games apiece.

The Cavs, who initially found themselves in a 2-0 series hole, had the momentum, the deafening roar of their home crowd behind them, and led by as many as eight points a few minutes into the third quarter. Their two best players, LeBron James and Kyrie Irving, were shooting well, and Cleveland was seemingly inhaling every rebound there was to be had.

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