Jayson Tatum is full of confidence that the Boston Celtics will bounce back against the Miami Heat and seal a place in the NBA Finals.

Jimmy Butler turned in one of the great playoff displays for the Heat on Friday as a 111-103 away win forced the Eastern Conference Finals series to Game 7, tied at 3-3.

Butler scored a playoff career-high 47 points, claimed nine rebounds and provided eight assists, with 17 of his points coming in the final quarter.

While the momentum might now be with the Heat, who have home-court advantage for the final game of the series, Tatum believes the Celtics can step up.

Asked what his confidence level was heading into Game 7, Tatum replied: "On a scale from 1-10 – 10. It shouldn't be any less than that, right? You know, it's the last game. This is what it's all about. 

"On a scale from 1-10, it's a 10 for my confidence level in myself and the group.

"It's no secret, it's Game 7. A trip to the NBA Finals – there's a lot on the line.

"A couple of us have been in this situation before, so we know what's at stake, we know how much this means to everybody. We know that going into the game."

Tatum led the way for Boston, scoring 30 points and finishing with nine rebounds and four assists, though he only made one shot in the fourth quarter while Butler took hold at the other end.

"I think it was just in the flow of the game, and how the game was going," Tatum said.

"Obviously I've got to watch the film, and things like that, but I think being out there, and the feel of the game, I was drawing a lot of attention.

"I was trying to find a mismatch, obviously, and when I find it, they sent a double, so I'd find the open man. I think it was just kind of how the flow of the game was going."