The Miami Heat have every reason to be nervous after letting the Boston Celtics claw back into the series with another blowout victory.

Remember when it looked like there'd be a week with no NBA Playoffs because both Eastern and Western Conference Finals series would end in sweeps?

The Nuggets took care of business and dispatched the Lakers in four. The Heat were supposed to follow suit with the Celtics and set up a "Battle of the Underdog Stories" in the NBA Finals.

Boston has made that clean narrative a whole lot more messy.

The Celtics trounced the Heat for the second game in a row, 110-97, to take the Eastern Conference Finals to Game 6 with Miami holding a suddenly tenuous 3-2 lead.

And yeah, the Heat should be worried. They'd be silly not to be.

Celtics have all the momentum going into Game 6 vs. Heat

Boston has upped their game since Game 3. They've shot 40 percent or better from three-point distance in the last two victories after shooting 35 percent or less in the opening three losses.

Miami took advantage of poor play from Boston to take such a huge advantage in the series, riding transcendent play from Jimmy Butler. Now Butler has faltered, producing his worst game of the playoffs in Game 5.

The Heat have gotten sloppy, committing 31 turnovers in Game 4 and 5 combined. Meanwhile, after giving the ball away 15 times in each of the first three games, Boston has taken care of the ball, committing 19 turnovers in total over the last two games.

All the Heat need to do is win one game. The overall advantage is obviously still in their hands. It's just that the margin is so much more narrow than it was. They've used up almost all of their wiggle room. If they lose Game 6, letting the series even up at 3-3, can anyone imagine them overcoming the shellshock to win a Game 7 in Boston?

That's why the worry has to be real.

The Celtics have been better on the road than they've been at home in the playoffs, and they just got one of two home wins they need in emphatic fashion. Pulling off a road win in Game 6 is not farfetched. Then it's a one-game coin flip for the trip to the Finals.

The saving grace for Miami is that Butler is still the x-factor for the series and he's been on more often than he's been off in the postseason. All he needs is one big night to get the job done.

As a counter, he's also expended a whole lot of energy to get the Heat here and there's a chance his magic has run out.

We've seen Boston respond admirably with the pressure on. Over the next one, or maybe even two, games we'll see how Miami does with the pressure turned back on them.

Suddenly, it feels like anyone's series again.

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