By Steve Keating

TORONTO (Reuters) - Wayne Gretzky emerged from the sidelines back into the hockey spotlight on Tuesday when he was introduced as the official ambassador to the NHL's Centennial Celebration.

Gretzky has largely remained in the hockey shadows in recent years and played no official role in the NHL since 2009, when he was a minority owner, coach and head of hockey operations with the Phoenix Coyotes.

The Great One's relationship with the NHL was left strained when the league purchased the team out of bankruptcy and squabbled with Gretzky over compensation.

The NHL’s all-time leading scorer, Gretzky will be front and center as the NHL celebrates its 100th anniversary with a number of events starting with the Centennial Classic, an outdoor game that will be staged in Toronto on Jan. 1 between the Maple Leafs and Detroit Red Wings.

"I’ve always said this thousands of times: it’s the greatest game in the world," said Gretzky, speaking to reporters ahead of Game One of the best-of-three World Cup final between Canada and Team Europe.

"Everything I have in my life is because of the National Hockey League and the game of hockey.

"So when the commissioner called me a couple months ago and asked me if I wanted to be involved I said, 'Absolutely.'"

The celebrations will bridge two seasons, 2016-2017 and 2017-18, culminating with special events around the anniversary of the league's founding on Nov. 26, 2017 and first games on Dec. 19.

While all plans have not been finalised, Gretzky will also lend his presence to the Winter Classic set for St. Louis on Jan. 2 and the All-Star weekend in Los Angeles from Jan. 25-27 where the 100 greatest players of all-time will be unveiled.

It would have been almost impossible to celebrate 100 years of NHL without Gretzky, who is widely regarded as the best player to ever lace up a pair of skates.

The Great One was a nine-times Hart trophy winner as the NHL's most valuable player.

He retired in 1999, ending his career after 20 record smashing seasons with most of the league scoring records which he still owns, including most goals (894), assists (1,963) and points (2,857).

His number 99 is first and only jersey to be retired by the league.

(Editing by Andrew Both)