Serious questions emerged from this disappointing meltdown that need to be answered immediately.
For one, where is the offense going to come from beyond Dwyane Wade?
If Michael Beasley and Jermaine O'Neal don't step it up in a big way, this will be a very short postseason for Miami. The same goes for Udonis Haslem, Quentin Richardson, and Dorell Wright; they're the x-factors in this matchup.
On the other side of the court, the defense that defined the Heat's 18-4 close to the regular season disappeared in crunch time; giving up 52 points in the paint doesn't help either.
So what happened?
Well, Beasley got dominated by Kevin Garnett and Haslem didn't fare much better. Tony Allen and Rajon Rondo had a field day with Carlos Arroyo and Mario Chalmers. Richardson held his own against Paul Pierce for the most part, but that's a battle that Miami just won't win for a full 48 minutes.
The Heat let the Celtics crowd the paint all night and weren't able to get much help defense from O'Neal and Joel Anthony.
For a team that prides itself in hard-nosed, high-energy defense, the will and desire just wasn't there down the stretch.
Boston, on the other hand, looked like a flashback to their 2007-08 championship season. They showed the type of heart and intensity that defines winners. A lot of teams would have folded down 14 points in the second half. The Celtics responded with force. They simply refused to lose.
If Miami wants to have a chance in this series, they need to match that intensity and desire. And it needs to start on Tuesday in a pivotal Game Two.
Historically, the chances of coming back from an 0-2 hole in a best of seven series is about four percent. Only 13 of the 204 teams that have been in that position have ended up winning the series.
Based on the way Boston played in Game One, Miami can't afford to try and join that short list of comeback teams. Game Two is a must-win for the Heat, especially with Garnett suspended for the contest.
Miami can't let an advantage like that slip away.
Garnett was crucial on both ends of the court for the Celtics in Saturday's victory. He clearly intimidated Beasley, putting added pressure on Wade to score. But more importantly, he's a barrel of gasoline that ignites in the clutch and raises the level of intensity for his entire team.
Garnett is every bit as important to this franchise as Paul Pierce, and his absence will be noticeably felt.
Michael Beasley should have a chance to get back on track and build some confidence without Garnett toying with him like a child. The Heat should also be able to regain their control of the paint without the worst mismatch in the series.
Garnett will be back for Game Three, eager to make Miami pay. They can't afford to go into that game down 0-2.
This Heat team is better than it showed in Game One, especially as of late. Having Garnett on the sidelines for 48 minutes is exactly what they need to regain the momentum in the series and head back to the American Airlines Arena with the home-court advantage in their corner.
South Florida will be brimming with excitement if the Heat are able to pull of an upset in Boston on Tuesday. That energy will transfer to the stadium, the crowd, and the players.
Wade and Co. play at a different level when they have their fans at their back.
They need to win Game Two to make sure that happens.
It's do or die for the Miami Heat. Luckily, Kevin Garnett will be nothing more than a spectator in this one.