Pablo Carreno-Busta came back from a set down to mount a superb comeback against Hubert Hurkacz and win the first ATP 1000 event of his career on Sunday.

The Spaniard became the first unseeded player to win the tournament since Guilhermo Canas in 2002 after weathering an early storm to shock the eighth seed 3-6 6-3 6-3 in Montreal.

Having come through a gruelling semi-final encounter with Dan Evans to reach his first ATP 1000 final in singles, the Tokyo 2020 bronze medallist struggled to deal with his opponent's impressive slew of aces in the first set, and saw his serve broken in the sixth game.

But a ruthless start to the second set saw Carreno-Busta break early, racing out to a 3-0 lead and holding his nerve to keep the gap to his Polish opponent, who was chasing a second ATP 1000 crown.

World number 10 Hurkacz attempted to rally with a fine start to the third set, but another loss of serve effectively stalled his momentum and Carreno-Busta was able to take the victory.

The result marks a much-needed boost for Carreno-Busta, who suffered first-round exits at the French Open and Wimbledon after making the last-16 in Australia, with the U.S. Open set to start later this month.

Serena Williams is "one of the greatest of all time", says fellow tennis legend Rafael Nadal as the 23-time grand slam winner prepares to hang up her racquet.

The 40-year-old, one of the most decorated players in the history of the sport, signalled her intent to "evolve away" from the game in an interview with Vogue Magazine earlier this month, hinting at her retirement following the U.S. Open in September.

With just shy of two-dozen grand slam singles titles, Williams trails only Margaret Court for the all-time record of 24 crowns, and could equal her in her farewell appearance.

Nadal, meanwhile, lies one behind her after victory in the Australian Open and French Open this year took him clear of Novak Djokovic and Roger Federer to 22, though the former's win at Wimbledon has seen him close the gap again.

The duo are set to feature at this week's Western and Southern Open, where Williams will face incumbent U.S. Open champion Emma Raducanu, and the Spaniard - who will mark his return from injury - has nothing but praise for his fellow giant of the game.

"She is one of the greatest sports [people] of all time," he stated. "I feel lucky to share a tour for a long period of time with her.

"Of course, from a selfish point of view, it's sad that she's leaving the tour but, on the other hand, we can't thank her enough for all the things that she did for our sport.

"I think she's an amazing inspiration for a lot of people around the world and I think she deserves to choose whatever works for her better at this stage of her life.

"So I wish her all the best. Hopefully, we can keep seeing her around the tour because I always believe that our sport, or the sport in general, is bigger and better when legends are around and she is a legend.

"Hopefully, we can enjoy her in a different way around the tour."

Nadal was forced to withdraw ahead of the Wimbledon semi-finals earlier this year with an abdominal tear, and now faces a potentially nervy run through to the U.S. Open in terms of fitness.

But the 36-year-old is cautiously optimistic, adding: "I hope to be ready. That's what I'm trying to do. Try to be a little more conservative, but I hope I can be ready to play.

"Of course, I need some more days to analyse how things are going in terms of abdominal feeling.

"But things are going well for the moment, so hopefully I can manage to be ready. I'm excited. I want to play tennis again on the tour. I'm having a good season, I'm enjoying it, so I want to enjoy this week in Cincinnati."

Simona Halep secured victory against Beatriz Haddad Maia in the Canada Open final on Sunday, though was given a tougher test than she had otherwise experienced throughout the tournament.

The Romanian was a 6-3 2-6 6-3 victor, dropping a set for only the second time in the week, but standing firm in the clash that clocked in at over two hours.

That meant records for Haddad Maia, who has played the most WTA-level matches with three sets in 2022 (20) and spent over 12-and-a-half hours on the court at the Canada Open in 2022, more than any other player in a single WTA tournament this year.

Wimbledon semi-finalist Halep proved to be a step too far for the Brazilian, however, with the win marking her most significant honour since winning in Rome in 2020.

It was far from a vintage performance from the 30-year-old, who had nine double-faults in the match compared to Haddad Maia's two and left the door open for the South American - who was vying for victory in her first ever WTA 1000 event.

Halep had already clinched a return to the world top 10 by reaching the final in Toronto, the first time since her 373-week stint ended just over a week ago - which led to admissions that she considered calling it quits amid her decline.

A valiant comeback in 2022 has been one of the major stories of the calendar year though and, on the back of victory in Canada and a semi-final march at Wimbledon, will have high hopes for the U.S. Open.

Hubert Hurkacz will contest the second ATP 1000 final of his career after coming from a set behind to defeat world number five Casper Ruud 5-7 6-3 6-2 in the semi-final of the Canadian Open on Saturday.

It was an interesting clash of styles going into the contest, with Hurkacz expected to rely on his dominant serve, while Ruud is one of the game's top returners, so when Ruud responded to an early break and was the one serving up a storm, it spelled trouble for the world number 10.

Ruud landed 78 per cent of his first serves in the opening set, compared to 60 per cent for Hurkacz, and the Norwegian won 95 per cent of those points (20-of-21) to allow just one break point in the frame while creating four for himself.

As Ruud's serve began to falter – with his first serve accuracy and effectiveness both cratering in the second and third set – his game began to struggle to hold up to the metronomic consistency of Hurkacz, who won the ace count 18-to-eight.

After pulling the match even at one set each, Hurkacz took the contest by the scruff of the neck and won the first four games of the deciding frame to pull away.

Poland's Hurkacz – who won his only previous ATP 1000 final against Jannik Sinner at the 2021 Miami Open – will now face Pablo Carreno-Busta in the decider after the Spaniard prevailed in a three-hour war of attrition against Daniel Evans 7-5 6-7 (7-9) 6-2.

In a match that was close in every area, Carreno-Busta was slightly better, winning 68 per cent (68-of-100) of his service points compared to 60 per cent (66-of-110) for Evans, while committing just one double fault compared to the Englishman's six.

It will be Carreno-Busta's first ATP 1000 final appearance, with the 2021 Hamburg Open – an ATP 500 event – the only career title for the 31-year-old above the ATP 250 level.

Simona Halep came from a set behind to defeat seventh seed Jessica Pegula 2-6 6-3 6-4 in the semi-final of the Canadian Open on Saturday, booking her place in the final against Beatriz Haddad Maia.

Romania's Halep, the 15th seed, struggled to return Pegula's serve in the opening set, winning just 32 per cent (nine-of-28) of her return points while compounding her early issues with four double faults.

Whether Pegula began to run out of steam, or Halep figured something out, she had significantly more success against the American's serve the rest of the way, winning 55 per cent (12-of-22) of her return points in the second set, and 57 per cent (20-of-35) in the decider.

Halep has now won 11 of her past 13 matches, and Pegula is her third consecutive win against a top-25 opponent after defeating both world number 21 Jil Teichmann and world number 13 Coco Gauff in straight sets. 

While this will be Halep's 18th career WTA 1000 final, it will be Haddad Maia's first, after she emerged triumphant 6-4 7-6 (9-7) against 14th seed Karolina Pliskova.

She did not have a serving advantage against Pliskova, who won the ace count nine-to-one, but she was gritty, saving four of the six break points she faced, and refused to concede the second set after dropping the first three games.

Haddad Maia – the only Brazilian ranked inside the top-100 – has now beaten five consecutive top-25 opponents on her way to the final, including world number one Iga Swiatek, Olympic gold medalist Belinda Bencic and Canadian hometown hero Leylah Fernandez.

Two-time major winner Simona Halep continues to find form ahead of the upcoming US Open with a 6-4 7-6 (7-2) victory over Coco Gauff clinching her spot in the Canadian Open semi-finals.

Halep defeated 10th seed Gauff, who had beaten Naomi Osaka, Elena Rybakina and Aryna Sabalenka this week, in one hour and 47 minutes.

The Romanian 15th seed was broken five times and sent down eight double faults, but found the edge with speed, finesse and power.

The win means Halep has won the third most matches (36-10) on the WTA Tour this season, behind only top-ranked Iga Swiatek (49) and Wimbledon finalist Ons Jabeir (37).

Halep's improved form comes after she teamed up with Serena Williams' ex-coach Patrick Mouratoglou in April following a difficult 2021 season.

"Before I met him I was super down with my motivation," Halep told reporters. "I couldn't really work, keep working. I was almost done with tennis. He brought this fire back and the motivation. He trusted that I still can play good tennis and he transferred this to me."

The 2018 French Open and 2019 Wimbledon champion added: "Physically I'm good. Mentally I'm good, so I think it's all positive."

Halep, who won the Canadian Open in 2018, has reached the semi-finals for the fifth time in her career where she will take on seventh seed Jessica Pegula.

Pegula got past Yulia Putintseva 6-3 6-3 in one hour and 21 minutes. Qualifying for the last four at the Canadian Open for the second straight year.

Brazilian Beatriz Haddad Maia maintained her Canadian Open run, having ousted Swiatek in the third round and local favourite Leylah Fernandez in the second, with a 2-6 6-3 6-3 victory over Tokyo Olympics gold medalist Belinda Bencic in two hours and 11 minutes.

Haddad Maia became the first Brazilian to reach the semi-finals of a WTA 1000 tournament. She will face Karolina Pliskova in the semi-finals after the Czech 14th seed beat Qinwen Zheng 4-6 6-4 6-4.