The Boston Celtics ran away from the rest of the NBA in the regular season. So far, the playoffs have been more of the same. The team that won 64 games to claim the league’s overall top seed dumped the Miami Heat in five games, winning 118-84 on Wednesday night to advance to the Eastern Conference semifinals. In their four wins, the Celtics’ biggest leads were 34, 29, 28 and 37. “We got past the first step,” said Celtics guard Derrick White, who scored 25 points. “We don´t start the next series up 1-0 because of we did what we did here today.” Boston is the first team in the East to advance. It will meet the winner of the series between Orlando and Cleveland, which heads to Game 6 on Friday night with the Cavaliers up 3-2. “They´ve been the best team all season long. And in four of the five games, they played as such,” Miami coach Erik Spoelstra said. “They took control of this game. You could sense that they wanted this to end right now, tonight, and not let this thing get back to Miami. That´s a sign of a mature team.”