Known affectionately as 'Mr Game Seven', Los Angeles Kings right winger Justin Williams went against type by providing the defining moment of the Stanley Cup Final opener on Wednesday.

Williams broke the deadlock in overtime with a lovely shot to the top left corner over the outstanding New York Rangers goaltender Henrik Lundqvist to lift the 2012 champions to a 3-2 victory and an early lead in the best-of-seven series.

The 32-year-old Williams played a major role in getting the Kings into the NHL title series, taking his league-record tally to 14 points in Game 7 deciders as Los Angeles edged the Chicago Blackhawks in the Western Conference Final series.

However, Williams showed his hand early on Wednesday, providing an assist on Drew Doughty's game-tying goal in the second period and then scoring the winner himself after Rangers defenseman Dan Girardi turned the puck over early in overtime.

"Everything offensively usually starts in our zone and (Mike) Richards made a great play getting the puck out but we screwed up the three-on-two royally and fortunately ... we were able to turn the puck over and I was sitting in front of the net and made a shot," Williams said.

"Certainly not our best game by any standards, especially ours, but we were able to get it done. That's the most important thing."

While Williams played down his influence, team mate Doughty was quick to point out how much respect the Kings have for their Canadian-born star winger.

"I have said this many times that Justin is the most underrated player on our team by a mile," Doughty said of a player who has amassed nine points in his past seven games from four goals and five assists.

"He doesn't get enough credit for what he does. There are two guys on this team that I want to give the puck to and that's him and Kopi (center Anze Kopitar).

"When they have the puck, plays happen and as a defenseman you love to watch it and it gives you opportunities to jump in offensively, which you do.

"At the same time, he works very, very hard at both ends of the ice and shows a lot of leadership."

Kings defenseman Willie Mitchell summed up what most Kings fans and players were thinking when asked if Williams nickname should be changed to 'Mr Game One'.

"I would like to call him Mr One, Two, Three and Four," Mitchell said. "It takes four wins so if he can do that three more times that would be real nice."