Jimmy Butler put on a show as the Miami Heat topped the Milwaukee Bucks 115-104 in Game 1 of the Eastern Conference semi-finals in the NBA playoffs.

Butler posted a playoff career-high 40 points to lead the Heat past the top-seeded Bucks at Walt Disney World Resort in Orlando, Florida on Monday.

A five-time All-Star, Butler scored 14 of his points in the final quarter as fifth seeds the Heat upstaged Giannis Antetokounmpo and the Bucks.

Butler became just the third player in Miami's postseason history to have at least 40 points, following in the footsteps of Dwyane Wade and LeBron James.

Heat team-mate Goran Dragic added 27 points for Miami, whose 5-0 start to the playoffs is tied for the best ever by a team seeded fifth or lower, per STATS. The Washington Wizards also started 5-0 as the fifth seeds in 2015.

Despite outscoring the Heat 40-29 in the opening quarter, the Bucks were unable to hold on as the Heat's defence starred.

Reigning MVP Antetokounmpo had 18 points, 10 rebounds and nine assists for the Bucks, who were led by Khris Middleton's 28 points.

The Heat and Bucks will meet again in Game 2 on Wednesday.

Meanwhile, the Oklahoma City Thunder forced a Game 7 against the Houston Rockets after prevailing 104-100.

Facing elimination in the Western Conference opening round, veteran Chris Paul came up big for the Thunder with 28 points and seven rebounds.

Trailing 98-92 with just over four minutes remaining, former Rockets guard Paul was clutch for the Thunder, nailing a pair of three-pointers down the stretch to lift his team.

James Harden recorded 32 points and eight rebounds for the beaten Rockets, who face the Thunder in Wednesday's decider, while Russell Westbrook had seven turnovers against his former team.

Jazz face Nuggets

The Utah Jazz and Denver Nuggets will go head-to-head in Game 7 of their Western Conference first-round matchup on Tuesday. The Boston Celtics and defending champions the Toronto Raptors are also in action in Game 2 of their Eastern Conference semi-final series.