"They say there are two rules in politics," he said. "Never, ever be pictured with a drink in your hand and never swear. But this is a big ... day."
The sold-out crowd filling Staples Center burst into cheers at the mayor's unexpected use of the F-word.
Fox Sports West was broadcasting the rally. It soon cut into its broadcast to apologize for the language, without naming Garcetti.
Luc Robitaille, a member of the Hockey Hall of Fame and president of business operations for the Kings, went up to speak after Garcetti.
“Well, we told our players not to curse, thanks,” Robitaille said, looking back at the mayor and giving him a thumbs-up.
Two years ago, at the victory rally after the Kings won the 2012 Stanley Cup, goalie Jonathan Quick used the F-word three times in quick succession. He received similar cheers from the audience, and he also was on live television.
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Times staff writers Scott Gold and Ruben Vives contributed to this report.