Kevin Durant and Russell Westbrook combined for 41 points in the second half and the Oklahoma City Thunder rallied to beat Miami 105-94 in game one of the NBA finals.
Durant scored 23 of his game-high 36 points in the second half and Westbrook had 12 third-quarter points for the Thunder, who kept their home record perfect in the playoffs with their ninth win in a row at Chesapeake Energy Arena.
"I am just playing off my teammates and not trying to force anything," Durant said. "Everybody came to play and we stuck together."
Westbrook finished with 27 points and 11 assists while Serge Ibaka had 10 points and six rebounds for the Thunder, who are making their first NBA Finals appearance since 1996 when they were based in Seattle as the SuperSonics.
Game two of the best-of-seven series is set for Thursday in Oklahoma City.
"We showed a lot of toughness in the second half," said Thunder coach Scott Brooks. "Really battling and fighting for every possession. I give our guys a lot of credit. They did a great job of competing in the second half."
LeBron James had a team-high 30 points and Dwyane Wade finished with 19 points and eight assists for the Heat, who lost to the Dallas Mavericks in last year's finals. The Heat are chasing Miami's first NBA title since 2006.
Oklahoma City's 8-0 home mark over the first three rounds saw the Thunder storm through the Western Conference by sweeping the Mavericks, ousting the Los Angeles Lakers in five games and polishing off the San Antonio Spurs in six.
Durant, making his first appearance in the NBA finals, put on a shooting clinic in the second half, scoring 17 points in the fourth quarter.
The series is billed as three-time NBA Most Valuable Player James against three-time scoring champion Durant, who has bragging rights at least for now.
The Heat hope to silence the critics and prove they are capable of winning the titles expected of them when James, Wade and Chris Bosh came together in Miami in 2010.
James may not have matched Durant shot for shot in the fourth quarter but he was no slouch either, finishing with nine rebounds and four assists.
"We are confident team and it is a long series," said Heat coach Erik Spoelstra. "This group has resolve. Sometimes we have to grind it out but we have the toughness to be able to bounce back.
"We are a better team on defense than we showed tonight. When we are not defending we don't get the opportunities on the other side of the court."
Westbrook gave the Thunder their first lead of the game with 16 seconds to play in the third quarter by finishing off a three-point play to make it 74-73.
The Thunder outscored the Heat 27-19 in the third quarter and committed only two turnovers in the second half after making eight turnovers in the first half.
"When we defend, we are a very good team and when we don't we are average," Brooks said.
Miami came out of the gate as the quicker more confident-looking team Tuesday, scoring 10 of the first 12 points of the game as James finished with 14 points in the first half.
Durant got things going for the Thunder by scoring their first eight points of the game. It wasn't until halfway through the first quarter that someone other than Durant scored for Oklahoma City and that was a dunk by Ibaka to cut the Heat lead to 14-10.
The younger Thunder team looked uneasy to start the game making four turnovers in the first quarter but they recovered with a strong closing run to end the second quarter. Miami led by as much as 13 points in the first half but Oklahoma City cut the margin to seven, 54-47, at halftime.
"We were nervous I guess," Durant said of the slow start. "That is something that can't happen in the next game or the rest of the series."
The Thunder carried that momentum over into the start of the third quarter as the reduced their turnovers and defended the three point shot better in the second half.
Miami was six of 10 from beyond the arc in the first half but just two of nine from three point range in the second half.