Canada's Denis Shapovalov beats #1 seed Rafael Nadal

Canada's Denis Shapovalov beats #1 seed Rafael Nadal

As for Nadal, the performance was a big blow, not only as he failed to break Shapovalov six times in the third set but also missed the chance to regain his world number one ranking.

Shapovalov is the youngest player to beat a top-two player in an event, since the 18-year-old Serbian Filip Krajinovic who won against fellow Serbian and the then world No 2 Novak Djokovic in the quarter-finals of the Belgrade Open in 2010.

Top seed Rafael Nadal made short work of his opening assignment at the ATP Montreal Masters on Wednesday when he routed Croatian youngster Borna Coric 6-1, 6-2.

Shapovalov will play the victor of Wednesday's match between No 1 seed Rafael Nadal and 20-year-old Croatian Borna Coric.

It showed even more in a spectacular game of 14 minutes, 30 seconds in the third set, marked by ten scores 40-40, and that Shapovalov was ripped off to give himself a lead of 2-1 in the round, not without saving three balls of breakage to the passage. Nadal went up 3-0, but Shapovalov used two aces to fight back and complete the upset victory over the 10-time French Open champion.

A day after celebrating his 36th birthday, Federer played the aggressive game that has propelled him to five titles, including two grand slams, this year, attacking the net and rocketing second serves.

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.

And it came back to haunt him as Nadal broke back, silencing the home crowd, before levelling the match at 4-4. "He has great potential".

"I actually feel really happy because I know I can play a lot better". The win went down as one of the most memorable wins in Canadian tennis history. "I played really well in the big moments". The 29-year-old double faulted twice in his first service game and had difficulty handling Federer's pinpoint serves.

Nishikori, who received a first-round bye as the fifth seed, was undefeated against the Frenchman in their past three meetings, their 2 hour, 41 minute match at the Aviva Center being their first encounter since last summer's Rio Olympics quarterfinals. If they can play that way throughout the tournament, without Djokovic, Murray and Wawrinka there, its tough to see who can stop them.

In other action, Diego Schwartzman lost the first eight games of his match against American Jared Donaldson, but the Argentine rallied for a 0-6, 7-5, 7-5 victory.

Fourth seed Alexander Zverev won a battle of NextGen prodigies as he beat Nick Kyrgios 6-4, 6-3.

True, the Russian-born teenager (he was a one when his family moved to Canada) was lucky to escape four match points in his first-round contest against Rogerio Dutra Silva.