Denis Shapovalov, 18, is one of the youngest players in the top 200. (Paul Chiasson/The Canadian Press via AP)

Almost a decade before 18-year-old Denis Shapovalov became one of the brightest young stars on the men’s professional tennis tour, he was a tiny kid with long blonde hair posing for photos with Rafael Nadal and Igor Andreev ahead of their match at the 2008 Rogers Cup in Toronto.

Shapovalov, who was born in Israel but moved with his family to Canada at an early age, was at the Rogers Cup as a match mascot for his hometown tournament. He escorted Andreev onto center court, helped with the coin toss, shook hands with the players and posed for photos before the start of the match, which Nadal would win en route to claiming the event’s title that year.

Fast forward nine years and Shapovalov, now a fast-rising tennis sensation ranked No. 143 in the world, was back on the court with Nadal. Only this time, Shapovalov was Nadal’s opponent. In front of a roaring hometown crowd on Thursday night in Montreal that included Wayne Gretzky cheering him on, Shapovalov stunned top-seeded Nadal, 3-6, 6-4, 7-6 (7-4), to advance to the quarterfinals.

On Friday, Shapovalov followed that up by rallying from a set down to beat Adrian Mannarino, 2-6, 6-3, 6-4, and become the youngest player to reach a Masters 1000 semifinal.

“I think from the morning, I kind of made the focus for today’s match,” Shapovalov said after his victory Friday night. “Obviously it was a little bit hard with ATP and you guys [the media] coming up with those memories of when I was a little kid shaking Nadal’s hand. That was pretty funny.”

It’s no surprise that Shapovalov has had trouble falling asleep at night. Within a few days, his stock has skyrocketed and the kid from Richmond Hill, Ont. has become the major story of the tournament in a country hungry for another Grand Slam contender.

Before his breakthrough victory over Nadal, Shapovalov defeated 2009 U.S. Open champion and former top 5 player Juan Martin del Potro on Wednesday. Armed with an aggressive all-court game, the lefty has swung freely all tournament, especially toward the end of the match against the 15-time Grand Slam winner Nadal — a player whom Shapovalov said he “grew up watching.”

“It’s what I dreamed of all my life growing up, playing guys like Rafa, Roger [Federer], Andy [Murray],” Shapovalov said after beating Nadal. “You know, my dream came true today.”

In his post-match news conference, a frustrated Nadal lamented his loss, saying it was “probably the worst match of the year for me” because of the missed opportunity to regain the world No. 1 ranking. But still the 31-year-old Spaniard had praise for his much younger opponent.

“He played well,” Nadal said. “He has great potential. I wish him the best. He has everything to become a great player. He played with the right determination in the important moments.”

Shapovalov is among the wave of talented young players 21-and-under that the tour has promoted as the Next Gen. Two of those players — Shapovalov and 16-year-old Felix Auger-Aliassime — are from Canada.

He will next play Alexander Zverev, the 20-year-old Citi Open champ already touted as an heir to the Big Four, in the semifinal.

“I think just, you know, having to battle every day,” Shapovalov said when asked what he’s been most proud of this week. “I’ve had several tough matches. Just getting through it every day, it’s really motivating.”

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