Norris Cole played a big role off the bench with 107.
For a team with their noted big three, the Heat got a boost from a 23-year-old rookie. Cole made half of his 16 shots and came up with three steals.
LeBron James hit for 26 points and Dwyane Wade had a solid all-around game with 24 points, eight assists and four blocks for Miami. The Heat, who beat the Celtics in five games in the Eastern Conference semifinals last season, also received 18 points and 11 rebounds from Chris Bosh.
Ray Allen tallied 28 points for Boston, which is 0-2 for the first time since 2006. Rajon Rondo contributed 22 points, 12 assists and eight rebounds, but also accounted for seven of his team's 24 turnovers. Those giveaways led to 33 Miami points.