BROOKLYN — On those countless frosty afternoons on that sheet of dreams that was his backyard rink in Oakville, Ont., he had lived this moment as a kid so many times, been the difference-maker so many times.

Stanley Cup playoffs. Overtime. Everything on the line. The entire world watching.

And then, young John Tavares would score the game-winner.

The Great Canadian Dream.

What young boy in the Great White North didn’t fantasize about doing something like this one day?

Now, here he was, all these years later, on a Sunday night in late April of 2016, so far from the GTA, playing a National Hockey League postseason game in a basketball arena for a franchise that hadn’t won a playoff series in 23 years.

It was a stage that called for a hero.

And that special moment John Tavares had envisioned all those many years earlier finally came to fruition.

His Islanders had come into Game 6 of their first-round series against the Florida Panthers leading 3-2. But things were not going well. Thanks to a Jonathan Huberdeau goal in the first period, the hosts trailed 1-0 through 59 minutes of play.

Then came Johnny on The Spot Moment No. 1.

There was a scramble in front of the Florida net. Lying on his belly, Roberto Luongo thought he had swallowed the puck. Instead, it lay beside him. Not for long. Not after Tavares saw it and drained the two-foot putt to tie the game 1-1, sending the contest into overtime.

Cue Johnny on The Spot Moment No. 2.

Deep in the second overtime period, with players nursing weary legs and sagging shoulders, Tavares skated behind the Florida net and came out the other side. Luongo couldn’t get over. Wraparound. Goal. Game winner. Series winner. Dream achieved.

“I feel especially good for our fans,” Tavares said. “They have waited so long. But we can’t just accept this. Enjoy it tonight but then look to what’s ahead.

“As a kid growing up, you dream about scoring an overtime winner like this. But to do it is incredible. You just soak it all in. It’s about the team and the fans. I’m happiest for them.”

Standing across the dressing room, defenceman Johnny Boychuk noted how impressed he was with Tavares. Boychuk won a Stanley Cup with the Bruins in 2011. He knows quality when he sees it.

“Johnny elevated his game to another level,” Boychuk said. “And we’re all thankful he did.”

It was most famous goal in Islanders team history since David Volek scored at 5:16 of overtime in Game 7 of a second-round series against Pittsburgh on May 14, 1993, eliminating Mario Lemieux’s Penguins in the process.

“It’s hard to take it all in,” Tavares said afterward, the fans chanting his name. “It’s incredible.”

Having disposed of the Panthers in six games, the Islanders now advance to meet the Tampa Bay Lightning in the second round.

In a series in which there was so little to choose between these two teams, three of the four Islander victories came in overtime. No one should be surprised. This is the same Islanders franchise that owns the best post-season overtime record (33-14) in NHL history.

Of course, a significant chunk of those victories came a long time ago during the Islanders dynasty of the early 1980s when Bryan Trottier, Mike Bossy, Billy Smith and Denis Potvin were reeling off four consecutive Stanley Cup victories.

The Islanders, of course, had not advanced past the first round since 1993 when they disposed of Dale Hunter’s Washington Capitals and Mario Lemieux’s Pittsburgh Penguins before succumbing to Patrick Roy’s Montreal Canadiens, the eventual Stanley Cup champions.

When it comes to post-season dry spells, these two franchises have set the standard in mediocrity. The Islanders have not come out ahead in a postseason series in 23 years, the Panthers in 20.

To put that into perspective, Panthers defenceman Aaron Ekland wasn’t born when the Isles last triumphed in a series. He had been born, however, when the Panthers did it. He was four months at the time.

Tavares was two years old when the Isles last won a playoff series back in 1993. It wasn’t long after that that he started skating on that backyard rink, dreaming of one day being an NHL overtime hockey hero.

On Sunday night, it came true.