Thirteen years later, Kucherov is a two-time Stanley Cup champion (2020, 2021), a seven-time NHL award winner (the Hart Trophy twice, the Ted Lindsay Award twice, the Art Ross Trophy three times), and is four points away from passing Steven Stamkos to become the Lightning's all-time leading scorer.
Stamkos, who is in his third season with the Nashville Predators after playing 16 with the Lightning, holds the title -- for now -- with 1,137 points (555 goals, 582 assists) in 1,082 games, an average of 1.05 points per game.
Kucherov has 1,134 points (404 goals, 730 assists) in 887 games, an average of 1.28 points per game.
He has a chance to get closer to the record, if not break it, on Tuesday, when Tampa Bay visits the Vegas Golden Knights at T-Mobile Arena (10:30 p.m. ET; ESPN, SN+).
"Whether I stayed or left, I think it was going to happen at some point," Stamkos said. "It might have gotten pushed down the line a little longer, but I think if it's all said and done and 'Kuch' ends up a Lightning for life it would have happened at some point."
Kucherov is notorious around the NHL for his work ethic, his vision and his hockey brain.
"He marvels at Kucherov because I believe they have similar minds," said Cooper, who regularly talks with Gretzky, including about Kucherov. "Everybody gives a different challenge on how you coach them, and I think Wayne probably was no different when he played because expectations are higher and there are just so many demands on a player of that elite talent. But what Gretzky appreciates is all that goes on because I think a lot of people take it for granted. When you're the best everybody thinks, 'Well, it's easy,' but to be honest, it might be harder to be the best. That's why Wayne is so intrigued by Kucherov, because he sees similarities."
Cooper, Kucherov's only coach in the NHL, said the Russian forward's most unique talent is his ability to "think above the rim."
But it took Kucherov some time to figure out how to do that against the best competition in the world.
"It's like you can pass your driver's test, it doesn't make you a good driver. You still have to get behind the wheel," Cooper said.