James — who dealt with cramps in last season’s NBA Finals — opened the fourth quarter with a jumper to extend the run to 10-0, and Miami seemed well on its way. But he returned to the locker room a short time later, the cramps having flared up again.
‘‘Once you start cramping, there’s nothing you can do about it,’’ James said.
Nonetheless, the Heat found a way to finish without the MVP.
‘‘This was a great night,’’ James said.
NOTES: Wade passed the 15,000-point mark for his career early in the second quarter, becoming the 123rd player in NBA history to reach that mark, according to STATS LLC. ... Rondo had at least 10 assists for the 25th straight regular-season game. ... The Celtics allowed 62 points in the first half; they gave up 62 or more only seven times in 379 regular-season and playoff games over the past four seasons. ... Miami players wore sneakers with gold somewhere in the color scheme; James’ were primarily gold — in honor of the ring — and trimmed in white and red.