Nick Kyrgios' heartbreaking act after victory over Daniil Medvedev

Nick Kyrgios has sent a touching message to his sick mother after his incredible win over World No.1 Daniil Medvedev at the Canadian Open.

Kyrgios took down the Russian star in staggering scenes in Montreal on Wednesday, winning 6-7(1) 6-4 6-2 to continue his sparkling run of form.

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It marked the Aussie star's 14th win in his last 15 matches, with his only loss during that time coming in the Wimbledon final against Novak Djokovic.

It was also Kyrgios' third victory over Medvedev in four career meetings and his second victory over a current World No.1.

Moments after the victory, Kyrgios sent a poignant message to his mum - who is currently in hospital in Australia.

"Be strong Ma," he wrote on a courtside camera lens.

Speaking before Wednesday's match, Kyrgios revealed mother Nill was in hospital.

"It's hard to be away from Australia now. My mum is in hospital, my dad hasn't been very well," he said.

"People only see me winning, losing, throwing a racquet. They do not really understand the challenges that we players face in our personal lives."

Nill Kyrgios has been forced to remain in Australia while her son is overseas due to her health.

Speaking during her son's run to the Wimbledon final, Nill told the Sydney Morning Herald: "My kidneys are reaching very close to the end of their life".

She revealed she's booked in to get a kidney from her husband and hopes it will be compatible.

Kyrgios spoke last year about the personal toll of travelling around the world and the heartache of being away from his mother.

"My mum is not doing too well with her health," he said at the time. "I'd like to go back and see her."

Fans sent their well-wishes to Kyrgios and his family on Wednesday.

Nick Kyrgios' incredible win over Daniil Medvedev

After losing the opening set in a tiebreaker, Kyrgios had to dig deep and turned the match around with one incredible backhand pass to break Medvedev in the sixth game of the deciding set.

He broke the Russian for a second-straight service game before closing out the match to love after exactly two hours.

"I've had some success against him in the past and he's beaten me before so I feel like we know each others' games well," Kyrgios said.

"I'm not the type of player who goes into these matches looking at rankings or anything like that.

"It's just who I'm playing and what kind of ball they're giving me and today I had a very clean objective of how I was going to play - a lot of serve and volley, a lot of aggressive play from the back - and I executed better than he did on the day.

"That's all it came down to. He won the first set and I feel like I had opportunities there as well so hopefully I can keep this rolling."

Kyrgios, who next faces Australian No.1 Alex de Minaur for a place in the quarter-finals, isn't getting carried away despite firming as one of the US Open favourites following his rousing victory over last year's champion at Flushing Meadows.

"Look, a grand slam is much, much different to any other tournament," he said.

"If I was in this position of a grand slam, you've still got to win another set and that's not easy at all. He's a machine.

"He's the best player in the world for a reason and at a grand slam he's a totally different beast."

Earlier, American Tommy Paul pulled off the first big upset of the tournament by dispatching second-seeded Carlos Alcaraz of Spain 6-7(4) 7-6(7) 6-3.

Paul, the World No. 34, saved a match point in the tiebreaker and converted his fifth match point in the deciding set. The second-round match lasted three hours and 20 minutes.

Alcaraz, who was making his Canadian debut, fell to 15-3 in Masters 1000 tournaments this season.

In other early results, fourth-seeded Casper Ruud of Norway defeated Alex Molcan of Slovakia 7-6(3) 6-3 and eighth-seeded Hubert Hurkacz of Poland beat Emil Ruusuvuori of Finland 6-3, 6-7(4) 6-2.

Roberto Bautista Agut, the No. 14 seed from Spain, downed American Jenson Brooksby 7-5, 6-1 and Spain's Pablo Carreno Busta topped Denmark's Holger Rune 6-0, 6-3.

with agencies

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