Watch: Smith beats buzzer to give Cavaliers largest playoff halftime lead ever

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When it rains, it pours.

The Cleveland Cavaliers put the hurt on the Boston Celtics in the first half of Game 2 on Friday night, taking a commanding 72-31 lead into the locker room.

This bucket by J.R. Smith capped off Cleveland's reign of dominance, putting the defending champions up by 41 on the scoreboard, thus setting a new record for the largest halftime lead in NBA postseason history.

The previous record of 40 came back in 1987 when the Washington Bullets trailed the Detroit Pistons.

LeBron James was a plus-40 through two quarters, which is the highest plus-minus rating of his career for both the regular season and playoffs in a single half, as well as the best of any player in the last 20 years.

Boston converted just 26.8 percent of its shot attempts, while Cleveland nearly had as many 3-pointers (10) as the opposition did field goals (11).