The Miami Heat have now failed twice to close out the Boston Celtics. But Jimmy Butler is guaranteeing they'll get it done.

Jimmy Butler has his faults but a lack of confidence is not one of them.

He has repeatedly put the Heat on his shoulders this postseason, helping them secure the No. 8 seed in the Play-In Tournament, knocking off the No. 1 and No. 5 seeds in the Eastern Conference in back-to-back upsets and then helping his Heat take a 3-0 lead on the Boston Celtics. He's averaged 28.8 points, 6.7 rebounds and 5.5 assists per game in the playoffs and done it all with his typical unflappable swagger.

But, for the first time, the Heat are facing real adversity. The Celtics won Games 4 and 5 by a combined 30 points. Gabe Vincent is hobbled with a sprained ankle and suddenly the Celtics can't miss from beyond the arc (42.0 percent in their last two games). We've never seen a team come back from a 3-0 deficit but, given the circumstances, the Celtics may have as good a chance as any team we've seen now that they have momentum, homecourt for a potential Game 7 and these last two wins under their belt.

Jimmy Butler wants you to stop right there because he says it ain't happening.

Jimmy Butler is guaranteeing victory over the Celtics in the Eastern Conference Finals

https://twitter.com/NBAonTNT/status/1661934451440631819/video/1

"We can and we will win this series." That's a Broadway Joe level guarantee.

Game 6 is in Miami, Saturday night at 8:30 p.m. Vincent is listed as day-to-day and could make his return but don't be surprised if Butler takes this one firmly in hand in front of the home crowd, with a chance to make good on his promise and add another line to his postseason legacy.

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