It was the biggest blockbuster trade in sports history. The best player ever to compete in his sport dealt while still in his prime to a region with a brief and unremarkable history with the game.
California has established itself as a hockey hotbed hitting its stride. That never would have happened without the arrival of Gretzky.
"For him to come to Los Angeles was a head-turner. He was going to Hollywood, to the second- or third-largest city in North America. It was absolutely catalytic," USA Hockey executive director Dave Ogrean told NHL.com. "The fact of the matter is his presence had such an impact on the still young and incipient amateur hockey community in Southern California. All of a sudden, the greatest of great ones is right there in the backyard. He's on television in homes in Southern California and the whole country."
The announcement of Gretzky's arrival in Los Angeles made major waves locally. Before the trade, the Kings rarely drew more than 12,000 people into the Great Western Forum. By the 1991-92 season, they were the first team in L.A. sports history to sell out every home game. The sprawling city suddenly became taken with hockey, and more and more youth were being enrolled in the sport.
"It was an attention-getter. Who is this 'Great One?'" California Amateur Hockey Association president Steven Laing said. "A lot of it had to do with talking about him as a kid growing up playing hockey. It gave a lot of kids [in California] the idea that they could do that too. And it grew from there.
"It certainly helps [today] having three NHL teams in California, which you would think is unheard of for a West Coast state."
At the time of the trade, the Kings were the only NHL game in California. They were joined by the San Jose Sharks (1992) and the Mighty Ducks of Anaheim (1994).
With many of those Californian children who were part of the Gretzky-led boom now grown up, the true impact of the trade on hockey in the state is evident. Jonathon Blum, who was born less than six months after the trade and grew up in Long Beach, mere miles away from the Forum, was chosen 23rd by the Nashville Predators at the 2007 NHL Draft. That selection made him the first California-born-and-raised player to be taken in the first round of the draft.
Three years later, two California-born players were taken in the draft's opening round: Beau Bennett by the Pittsburgh Penguins and Emerson Etem by the hometown Ducks. And that's only the tip of the iceberg for an emerging California hockey program.
Across the hockey landscape, Californians are contributing at every level.
In 2002-03, there were 20 Californians playing Division I college hockey, which ranked the Golden State behind Alaska, Connecticut, New Hampshire and Wisconsin. By the 2012-13 season, California had leapfrogged each of those states with 59 Division I players, ranking the state seventh in the nation, according to College Hockey Inc.
Quinnipiac University, the top-ranked team in the country much of the season, featured three California-born players when it made its way to the Frozen Four championship game.
In perhaps the biggest win for California hockey since the Gretzky trade, Santa Margarita Catholic High School -- located less than 60 miles southeast of downtown Los Angeles -- won the USA Hockey National High School Championship in March.
Stanley Cup victories by the Ducks and Kings have contributed to this growth. But the seeds were planted with the Gretzky trade.
"It helped incredibly. If you look at youth hockey now in California, they can compare to teams back East. They're good players there," said Rogie Vachon, who as a former player and general manager with the Kings has been watching hockey grow in California for 40 years. "We knew having the best player in the game coming to Los Angeles [was big]. All of a sudden everything picked up. Parents were saying, 'Maybe my son should be playing hockey.' It created so much interest in California, it was incredible."
It was a seminal moment for hockey in the United States, something that was never considered at the time of the trade.
"I didn't put much thought into the long-term future at that time. It was all the other stuff," said former Kings owner Bruce McNall, the man largely credited with bringing Gretzky to Los Angeles. "Then you realized the impact it was going to have on youth hockey, the impact it was going to have on expansion and so forth down the road. It happened after the fact. At that time, there was no thought of it."
On the day the Gretzky trade made international headlines, any influence it would have on California hockey may have been an afterthought. But 25 years later, that growth may be its enduring legacy.