I think Boston has the better perimeter defense and a strong balanced attack and with their experience I'll back them in game 1 on Tuesday.
Boston's Brad Stevens is 8-1 in his last nine postseason series openers while Miami's Erik Spoelstra is 14-10 lifetime in such contests
Boston kept Toronto under the 100-point mark in all four of its conference semifinal victories, including in a 92-87 Game 7 success. The Heat and Celtics rank 12th and 13th, respectively, out of the 16 playoff participants in pace of play (possessions per game). The Heat aren't going to get the same 3-point looks they got versus the Bucks. In the playoffs, Boston is holding opponents to 30 percent from beyond the arc. Look for Miami to show a bit of rust and struggle to adjust to the Celtics' versatile, elite tough defense. Take the Celtics in game 1.