James and Dwyane Wade led a group of teammates to the celebration early Friday at the Liv nightclub in the Fountainebleau Hotel in Miami Beach, the South Florida Sun-Sentinel reported.
The players were accompanied by team owner Micky Arison.
Partygoers reported James took to the stage to rap to Jay-Z and Kanye West's "Ball So Hard," "All I Do is Win" by Miami's DJ Khaled and Queen's "We Are the Champions."
The Heat beat the Thunder 121-106 in Game 5 of the championship series Thursday night.
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