Brett Brown has something called a "pre-mortem" in which he diagnoses the things that could go wrong with his team and lead to a loss in a given game. I like the term, and I like the concept, so let's do a quick pre-mortem for the Sixers in Game 2.
If the series heads back to Miami tied, 1-1, these are some of the potential reasons:
1) Their advantage from three-point range disappears. To a certain extent, this is almost a given. In connecting on 18 of 28 shots from downtown in Game 1, the Sixers turned in one of the best long-range shooting performances in NBA playoff history. The last time a team attempted at least 28 shots from downtown and connected at a rate of 64.3 percent or better was 2002, when the Celtics did it against the A.I.-led Sixers. Other than that, it has happened only one other time (1995 by the Rockets).
Best playoff single-game three-point shooting percentage, NBA history (minimum: 20 attempts)
1. Knicks at Cavs, 1996, .773 (17-of-22)
2. Sonics v. Rockets, 1996, .741 (20-of-27)
3. Pistons v. Cavs, 2006, .682 (15-of-22)
4. Rockets at Jazz, 1995, .679 (19-of-28)
5. Celtics vs. Sixers, 2002, .655 (19-of-29)
6. Sixers vs. Heat, 2018, .643 (18-of-28)
During the regular season, the Sixers' median single-game three-point percentage was .377, which equals about seven fewer makes on 28 attempts. That means that in their 130-103 win over the Heat in Game 1, they scored an extra 21 points than they would have on a "normal" shooting night. That's not perfect math: we'd have to factor in the number of offensive rebounds they might've collected, etc.
On the flip side, the Heat also shot the lights out in Game 1, hitting 12 of 26 shots from downtown for a .462 conversion rate that was well above their median of .357 for the season, or the equivalent of about three extra makes. That still means the Sixers had a +12 advantage, all other things remaining equal. But that still accounts for less than half of their final margin of victory.
2) They turn the ball over and don't crash the offensive glass. The most impressive aspect of the Sixers' victory might've been the way they took care of the ball. Ben Simmons had five turnovers by himself in the first half, but the Sixers as a team finished the game with just 10. To put that in perspective, they had 10 or fewer turnovers in just nine of their 82 regular-season games.
The Sixers also finished Game 1 +7 in offensive rebounds. Along with their +6 advantage in turnover margin, they effectively enjoyed the benefit of 13 extra possessions. In fact, they finished the game with 17 more attempts from the field and just two fewer attempts from the foul line. In the Heat's two wins over the Sixers in the regular season, they were outrebounded on the offensive glass, 19-17. In their two losses, they were outrebounded by 32-19.
3) The thing I can't figure out is where the Heat's offense is going to come from. The Sixers had some problems in the first half guarding James Johnson off the dribble — he beat Saric several times. Maybe that is a matchup the Heat can look to a little more. Really, though, 103 points are about what you can expect from this Miami team. They averaged 102.5 in their four regular-season games against the Sixers and just 105 points in the two that they won. Their problem in Game 1 was their inability to deal with JJ Redick's frenetic off-the-ball movement and the screens that the Sixers bigs were setting. It wasn't just the 28 points Redick scored on 8-for-13 shooting — a considerable chunk of Dario Saric's and Ersan Ilyasova's 37 points came off on plays in which the Heat defense was preoccupied with Redick.
The reality is, the Heat aren't a team that can give up 130 points and expect to win. In the regular season, they were just 2-16 when allowing 115+ points and 3-23 when allowing 110+. It will be really interesting to see what kind of adjustments Erik Spoelstra makes on that end of the court. While Simmons had his usual game, he wasn't the Heat's biggest problem. They opened the game with slender three-man Josh Richardson guarding him, and that did not go well. Every time Simmons had Richardson in his sights, he lowered his shoulder and went hard to the rim, encountering little resistance. After the Sixers took a 17-12 lead, Spolestra called a timeout and changed things up, putting four-man James Johnson on Simmons. By the end of the game, Justise Winslow was drawing primary duties: Winslow played the final 18:29 of Game 1 after coming off the bench.