Jayson Tatum registered 26 points, 10 rebounds and six assists to help the Boston Celtics notch a 100-96 victory over host Miami Heat to win game seven of the Eastern Conference finals.

Tatum was named conference finals MVP as the Celtics broke the tied finals series and advanced to the NBA Finals for the first time since 2010.

Jimmy Butler recorded 35 points and nine rebounds to lead the Heat, but unlike in game six, his individual heroics were not enough for Miami.

Butler missed a three-point attempt with 16.6 seconds left that would have given Miami the lead.

The Celtics will face the Golden State Warriors in the NBA Finals, which start on Friday (AEST) in San Francisco.

Boston led wire-to-wire in ending a streak of five straight losses in opportunities to clinch an NBA Finals berth.

The Heat, who trailed by 17 early in the second quarter and by 16 late in the second, pulled within 82-79 after Bam Adebayo and Butler opened the fourth quarter with baskets.

But Boston countered with eight straight points, with Marcus Smart's floater making it an 11-point cushion with 6:36 left.

Smart's two free throws elevated the lead to 98-85 with 3:35 remaining.

Miami suddenly came alive as Kyle Lowry, Max Strus and Victor Oladipo scored baskets to cut the deficit to seven.

Lowry's lay-up with one minute left pulled the Heat within 98-93 and Strus followed with a three-pointer to cut the deficit to two with 50.7 seconds left.

Miami had a chance to move ahead, but Butler's ill-fated 3-pointer bounced off the rim and Smart made two free throws with 11.4 seconds left to give Boston the game-ending four-point lead.

Miami's Tyler Herro (groin) returned from a three-game absence but was scoreless in seven minutes.

Reuters