How Celtics can position themselves to make NBA history vs. Heat: ‘All that matters is the next game’

MIAMI — Marcus Smart said it at the Boston Celtics’ morning shoot-around prior to Game 4 of the Eastern Conference finals: “Don’t let us win one.” Well, they got the one. The Celtics caught fire in the second half on Tuesday and got out of Miami with a 116-99 victory against the Heat, trimming their series deficit to 3-1 and continuing an impressive streak with their backs against the wall. Over the last two postseasons, Boston is now 6-0 when facing elimination against Eastern Conference competition. They’ll have to run that mark to 9-0 if they’re going to get out…