"When your captain can come out and play that type of game tonight, it sets the tone for everybody," Kings coach Todd McLellan said.
Kopitar is the 12th NHL player since 1967 with at least five points in a season opener. Kevin Stevens holds the record in the expansion era (since 1967-68) with six points (two goals, four assists) for the Pittsburgh Penguins on Oct. 5, 1990.
Kopitar completed his hat trick at 15:06 of the third period, scoring on a backhand on a 2-on-1 rush from Viktor Arvidsson in his Kings debut to make it 6-1. It was the third hat trick in a season opener in Kings history, with Kopitar joining Luc Robitaille (Oct. 6, 1988) and Jari Kurri (Oct. 4, 1991).
"You just try to stay in the moment, really," Kopitar said. "You don't think about that too much. I mean, just play. Like I said, it's first game of the season, so first and foremost, we wanted to get off to a good start and get the two points in the bank and just kind of go from there."
Drew Doughty had a power-play goal and three assists, Phillip Danault scored in his Kings debut, and Vladimir Tkachev had two assists in his NHL debut. Cal Petersen made 23 saves for Los Angeles.