Stefanos Tsitsipas has indicated he will only get the COVID-19 vaccine if it becomes mandatory to participate on the ATP Tour.

World number three Tsitsipas revealed he has not yet been jabbed against coronavirus with the tennis world divided on the issue. 

The ATP Tour have publicly encouraged players to get vaccinated, but Novak Djokovic is among the high-profile players to have stated it should not be compulsory to compete.

When asked ahead of the Western and Southern Open if he would get the vaccine, Tsitsipas told a media conference he still had reservations.

"No one has told me anything. No one has made it a mandatory thing to be vaccinated," the Greek said.

"At some point I may have to, I'm pretty sure about it, but so far it hasn't been mandatory to compete, so I haven't done it, no."

Tsitsipas received a bye through to the second round in Cincinnati, where he will play either Sebastian Korda or Laslo Dere.

The 23-year-old, who has a tour-high 45 wins this season, climbed up to third in the world rankings last week and boldly targeted overhauling Djokovic in top spot.

"The rankings are there for a reason. They signify something important," he added.

"I think that the very next step would be the number one spot, which I hope I can get to one day.”

Andy Murray looked sharp in his first singles match since Wimbledon, rolling to a straight-sets win over Richard Gasquet at the Western and Southern Open. 

Murray defeated the veteran Frenchman 6-4 6-4 on a rainy opening day in Cincinnati, capitalising on a strong service game to advance. 

Murray had 14 aces to just two double faults and won 81 per cent of points on his first serve while saving four of the five break points he faced. 

A two-time champion at the ATP 1000 event, he will face the winner of Tuesday's match between Alejandro Davidovich Fokina and ninth seed Hubert Hurkacz in the second round. 

Two players who shared a birthday Monday also prevailed on their big day. 

On the day he turned 20, 11th seed Jannik Sinner defeated Federico Delbonis 6-2 7-5, while 10th seed Diego Schwartzman had to work a bit harder on his 28th birthday to down Daneil Evans 6-2 4-6 6-3. 

Elsewhere, 12th seed Felix Auger-Aliassime beat Marton Fucsovics 7-6 (7-0) 6-3, while 14th seed Alex de Minaur rallied to down Filip Krajinovic 0-6 6-4 6-4. 

Fifteenth seed David Goffin fell 6-3 6-3 to Guido Pella in the only seeded upset of the day. 

Other winners Monday included Karen Khachanov, Fabio Fognini, Lloyd Harris, Dominik Koepfer, Benoit Paire, Albert Ramos Vinolas and Mackenzie McDonald. 

Among those set to play their opening matches Tuesday are third seed Alexander Zverev, who will face Harris, and sixth seed Denis Shapovalov, who plays Paire. 

Daniil Medvedev lived up to his top-seed billing by overcoming Reilly Opelka in straight sets in the National Bank Open final.

World number two Medvedev prevailed 6-4 6-3 in Toronto on Sunday as he became the first Russian to win the ATP tournament since Marat Safin in 2000.

Medvedev now holds four of the nine ATP Masters 1000 titles, having also previously come out on top in Cincinnati, Shanghai and Paris.

He saved all four break points faced against unseeded Opelka, who stunned Stefanos Tsitsipas in the semi-finals, and needed just 85 minutes to complete the job.

Reflecting on his latest tour triumph, Medvedev said: "I could not have dreamt of this at one point.

"With Novak [Djokovic] and Rafael [Nadal] playing, it seemed like an untouchable achievement. Now I have four wins in five finals, which is a good score. I am just happy. 

"Playing Canada and Cincinnati, the goal is to win as many matches as possible. I was able to do it two years ago and I will try and do it again."

Opelka was competing in his maiden final at this level and started strongly, racing 40-0 ahead in the fourth game with some powerful hitting.

However, the 23-year-old – the first American to reach the final since Mardy Fish in 2011 – could not break his opponent as Medvedev recovered with some impressive serving to take the game.

Medvedev earned the first break in the following game and comfortably held to take the first set.

The Russian forced Opelka into errors in the second set and reeled off nine points in a row en route to breaking his opponent in the third game.

It was plain sailing from that point on as two-time beaten grand slam finalist Medvedev eased over the line to add another trophy to his collection.

Top seed Daniil Medvedev will face Reilly Opelka in the National Bank Open final after the American stunned Stefanos Tsitsipas in a three-set classic in Saturday's semi-finals.

World number 32 Opelka fought back from a set down in Toronto to knock out favoured third seed Tsitsipas in two hours and 32 minutes.

The 23-year-old American triumphed 6-7 (2-7) 7-6 (7-4) 6-4, booking a spot in his first ATP Masters 1000 final.

Opelka sent down 17 aces but also hit 27 groundstroke winners in the shock victory over 2021 Australian Open semi-finalist Tsitsipas who had beaten in-form Casper Ruud in the quarters.

"I played great," Opelka said in his on-court interview. “These courts suit my game, it is no coincidence that John Isner is in the other semi-final.

"Stefanos has definitely improved his returning. Come 5-5 in the first set, a lot of balls started to come back. He is a thinker and has a high tennis IQ, so it was expected, but that is what separates him from the rest of the pack."

Opelka was aided by an excellent first serve percentage of 72 per cent, winning 62 of 81 points when he made his first serve.

Both first two sets went to tiebreaks, with Tsitsipas failing to generate a break point until the third set. Opelka made the first break of the match in the seventh game of the third set and held serve twice after to seal victory.

World number two Medvedev cruised into the decider with a commanding win over John Isner in less than an hour.

Medvedev, who was runner-up in Toronto in 2019, won 6-2 6-2 over the big-serving American, with the match totaling 54 minutes.

Isner could only manage four trademark aces for the match, while the Russian had 11 and broke the American four times from seven opportunities.

Casper Ruud continued his excellent winning streak while Stefanos Tsitsipas made it a birthday to remember at the National Bank Open in Toronto.

Tsitsipas turned 23 on Thursday and marked the occasion with a 6-3 6-2 win over Karen Khachanov.

The Greek star was presented with a cake by tournament officials after his win, as the crowd serenaded him with a chant of 'happy birthday'.

It marks a significant improvement on when Tsitsipas turned 20. On that occasion, he lost the 2018 final of this event to Rafael Nadal.

Next up for Tsitsipas is Casper Ruud, who poked fun at his critics after he eased into the quarter-finals.

Ruud, the world number 12, won three titles on clay courts in July and has now continued that form in the ATP Masters 1000 event.

Playing on a hard court has proved no challenge for the in-form Norwegian, who wrote 'Hard Courts' with a smile underneath on the camera after his 6-4 6-3 victory over Dusan Lajovic on Thursday.

"I have seen a lot of people questioning my ability to play on hard court, so I just thought it was funny to write a little note," Ruud said in a news conference.

"I think it's fun to play on hard courts. Even though I (have achieved) most of my best results on clay, my best slam result is from this year’s Australian Open (where he reached the Round of 16), so I think it's a surface that also can suit my game well even though this year has been mainly clay.

“I think I'm motivated to come back to the hard courts. I have had two very good matches here. It's a great start for me to the hard-court swing."

Ruud, in the hunt for his fifth title of 2021, has won the only previous meeting between the duo.

"[I am] looking forward to that battle," Tsitsipas said. "We have played each other in the past. Not an easy guy to play against. Looking for a change, looking for a switch-up this time."

However, there was no place in the last eight for world number seven - and Olympic gold medallist - Andrey Rublev, who went down 7-5 7-6 (7-5) to American John Isner.

Fresh from a triumph in Atlanta, 36-year-old Isner has looked sharp all week and has now won eight successive matches.

It brings up a third quarter-final appearance for the world number 30 in Canada, and he will play French 11th seed Gael Monfils after he got past lucky loser Francis Tiafoe 6-1 7-6 (7-2). Monfils will be competing in his first ATP Tour quarter-final in 18 months.

Top seed Daniil Medvedev proved too good for Australian qualifier James Duckworth, winning 6-2 6-4 in one hour and eight minutes.

Medvedev was in ominous form on the hard court, sending down 10-1 aces and winning 27 of 32 points on his first serve.

The Russian world number two will play seventh seed Hubert Hurkacz who fought back to win 6-7 (7-9) 6-4 6-4 over Nicolas Basilashvili.

Eighth seed Diego Schwartzman lost in three sets to 10th seed Roberto Bautista Agut after the Spaniard saved three match points.

Bautista Agut will next play Reilly Opelka who came from behind, and also saved a match point, to win over Lloyd Harris in three.

Canadian fifth seed Denis Shapovalov was a major casualty in the second round of the National Bank Open in Toronto after a straight-sets defeat to Francis Tiafoe.

Unseeded American Tiafoe swept aside the local 6-1 6-4 in one hour and 15 minutes to secure his third-round spot against 11th seed Gael Monfils who beat John Millman 3-6 6-3 6-4.

Tiafoe was only in the Toronto main draw as a lucky loser after being defeated in qualifying by Emil Ruusuvuori but he hit 14 winners in an emphatic display.

World number 10 Shapovalov was unable to generate any break points while Tiafoe reeled off five games in a row, with two breaks, to win the first set.

The Canadian continued to struggle with his serve in windy conditions, as the American world number 52 won 88 per cent (23/26) of points on his first serve.

Another local hope, ninth seed Felix Auger-Aliassime, also was eliminated, going down 7-5 6-4 to Serbian Dusan Lajovic.

The Canadian hit six aces to Lajovic's none, but was undone by unforced errors at key times, with a double fault gifting the Serbian a 6-5 lead in the opening set.

Australian 12th seed Alex de Minaur also bowed out after a one-sided 6-1 6-1 defeat to Georgian world number 42 Nicolas Basilashvili.

Basilashvili sent down 6-2 aces and converted five of his six break points generated in an impressive display.

Australian qualifier Jack Duckworth booked a third-round ticket against top seed Daniil Medvedev after upsetting 16th seed Jannik Sinner, who won last week's Citi Open.

Fourth seed Andrey Rublev won through with a 7-6 (7-4) 6-3 victory over Fabio Fognini, while seventh seed Hubert Hurkacz progressed with a walkover after Kei Nishikori retired with a shoulder injury.

Eighth seed Diego Schwartzman beat Benoit Paire 7-5 6-1, while 10th seed Roberto Bautista Agut handled Tommy Paul 6-3 6-4.

John Isner knocked out 13th seed Cristian Garin in three sets, while Lloyd Harris beat Feliciano Lopez in two and Karen Khachanov defeated compatriot Aslan Karatsev 7-6 (9-7) 6-4 to secure a third-round meeting with third seed Stefanos Tsitsipas.

Tsitsipas pledged to help those affected by the fires in his homeland in his post-match press conference on Tuesday.

“My heart is with all the people of Greece,” Tsitsipas said. “I come from the south suburbs of Athens. When I was there a few days ago, I could see the fires from the south. Huge, giant clouds, smoke, which you could see from far, far away. It wasn't very nice. Even at the beach that day when I went to swim, you could see all the debris from the smoke and from the fires in the sea.”

Daniil Medvedev and Stefanos Tsitsipas survived three-set scares at the National Bank Open on Tuesday, but five-time tournament champion Rafael Nadal departed Toronto without even taking the court. 

Top seed Medvedev, who won just three games against Nadal in the final in 2019, the last time the tournament was played, prevailed 4-6 6-3 6-4 in his opener against Alexander Bublik.

The man Nadal beat to win the title the previous year, Tsitsipas, failed to convert on five match points in an epic second-set tiebreak but recovered to down Ugo Humbert 6-3 6-7 (13-15) 6-1.

Nadal pulled out ahead of a scheduled match against Lloyd Harris, who beat him last week in Washington as the 20-time grand slam winner struggled with a foot injury. 

Countryman Feliciano Lopez replaces Nadal in the draw and will face Harris on Wednesday. 

Elsewhere Tuesday, sixth seed Casper Ruud needed more than two hours to put away Marin Cilic 6-3 3-6 6-3, while 14th seed Grigor Dimitrov suffered a quick 6-3 6-4 exit against big-serving American Reilly Opelka.

A pair of unseeded veterans advanced, with 2016 finalist Kei Nishikori a 6-4 6-7 (5-7) 6-2 winner over Miomir Kecmanovic and John Isner defeating Alejandro Davidovich Fokini 6-4 6-1 in just over an hour.

Two days after appearing in his first ATP Tour final at the Citi Open, Mackenzie McDonald fell 6-3 6-4 to Benoit Paire in his Toronto opener. 

In other first-round matches, Karen Khachanov beat Cameron Norrie 6-4 5-7 6-4, Frances Tiafoe downed Yoshihito Nishioka 6-4 6-3, Dusan Lajovic handled Emil Ruusuvuori 3-6 6-3 6-3 and Nikoloz Basilashvili defeated Jenson Brooksby 2-6 6-0 6-4.

Rafael Nadal has withdrawn from the National Bank Open ahead of his opening match due to a left foot injury.

The Spaniard made a return to action on the ATP Tour last week at the Citi Open, his first outing since suffering defeat to Novak Djokovic in the semi-finals of the French Open in June.

His comeback was aimed at getting prepared for the US Open but, having lost in the last 16 in Washington to Lloyd Harris, he will not now be participating in Toronto.

"I really wanted to play here a lot, but now is the moment to make a decision, and this is unfortunately the decision that I have taken," Nadal told the media.

"I have had this issue for a couple of months, as people know.

"Of course, it is not a happy situation after all the success that I had here in Canada, not being able to play this year after missing a year. It's a tough one, but that's how it is today."

Nadal skipped Wimbledon citing the need to recover after the clay season, while the left-hander also opted out of representing his country at the Tokyo Olympics.

The five-time champion in Toronto was scheduled for a repeat meeting with Harris in the second round. Instead, his place in the draw goes to compatriot Feliciano Lopez.

South African Lloyd Harris booked a second-round date with Rafael Nadal at the National Bank Open after a straight-sets win over Canadian qualifier Brayden Schnur on Monday.

World number 49 Harris eased past Ontario-born Schnur 6-3 6-2 in one hour and 17 minutes in Toronto.

Harris sent down nine aces, winning 78 per cent of points on his first serve, converting four from four break points on return.

Nadal is a five-time champion in Toronto, winning the previous two editions in 2018 and 2019.

Marin Cilic, who won his first title for three years in Stuttgart, beat Albert Ramos-Vinolas 6-2 4-6 6-3 in two hours and 13 minutes.

The 32-year-old will face sixth seed Casper Ruud in the next round.

Fabio Fognini also needed three sets to progress, battling from behind to defeat Jan-Lennard Struff 6-7 (2-7) 6-2 6-4 to set up a meeting with Andrey Rublev.

Ugo Humbert impressed in his straight-sets defeat of Lorenzo Sonego and will next face third seed Stefanos Tsitsipas, while qualifier James Duckworth beat Taylor Fritz to secure a showdown with Citi Open winner Jannik Sinner.

Alexander Bublik defeated Briton Dan Evans in straight sets to earn a second round meeting with top seed Daniil Medvedev, while Australian John Millman will face 11th seed Gael Monfils after beating Ricardas Berankis.

Reilly Opelka came from a set down to win over Australian Nick Kyrgios, while Tommy Paul also fought back to beat Canadian Vasek Pospisil.

Roger Federer has withdrawn from both the Canadian Open and Cincinnati Masters as he continues to recover from a knee injury.

After undergoing two operations on his right knee last year, Federer has competed in just five events so far in 2021.

Most recently, the 20-time Grand Slam champion reached the Wimbledon quarter-finals, before losing in straight sets to an inspired Hubert Hurkacz.

The 39-year-old then missed the Olympic Games due to what he described as a "setback" with his knee.

He was scheduled to appear in Toronto and Cincinnati – where he is a seven-time winner – and step up his preparation ahead of the US Open.

However, his participation in the final Slam of the year is now uncertain after he pulled out of this month's ATP Masters 1000 tournaments.

Another player who will not be competing in Toronto is Alexander Zverev; the Olympic gold medallist also opting to withdraw.

In a statement, he said: "Due to the intense past couple of weeks and my incredible experience at the Olympics, I need to recover so that I can hopefully be at my best for the remainder of the U.S. summer swing.

"It was a difficult decision for me as I have had great memories from Canada and I can't wait to be back next year!"

Novak Djokovic dug deep in the face of fierce Roman resistance to set up a showdown with Rafael Nadal in the men's final at the Internazionali d'Italia.

World number one Djokovic came from a set down overnight to beat Stefanos Tsitsipas 4-6 7-5 7-5 early on Saturday, before returning to the court to face Italian Lorenzo Sonego in the evening.

The Rome crowd raucously rallied behind Sonego, who beat Andrey Rublev earlier in the day, and the 26-year-old rose to the challenge but eventually fell to a 6-3 6-7 (5-7) 6-2 defeat.

Djokovic had match points before serving for it at 6-5 in the second set, yet it was to prove a stirring game as the noisy home crowd encouraged Sonego, who snatched a gutsy break. The tie-break looked set to be wholly one-sided when Djokovic raced 3-0 ahead, but it was soon back on serve, partisan spectators at the Foro Italico roaring in delight at a double fault from the Serbian.

From 4-2 behind, Sonego surged to 6-4 ahead in the tie-break. He failed to convert a first set point when ripping a forehand into the net, but the set was his when Djokovic sent a backhand service return long.

Sonego then had 0-40 against the Djokovic serve at the start of the decider, but he could not force the break, and the top seed gained strength from that escape, eventually cruising to victory.

Five-time Rome champion Djokovic said on Amazon Prime: "I bounced back very well after the second set. Maybe if he started with a break up in the third, things would look differently. I also had my chances and I only had myself to blame for not closing the match in straight sets.

"But he's a quality player, very dynamic, it's not easy to play against him and obviously he had the crowd behind him. It was an electric atmosphere. In the end I managed to close out the match really well."

Looking ahead to tackling Nadal, Djokovic said: "I need to recover. Hopefully I'll have fresh legs because that's what I definitely will need and it's necessary to have a chance against Rafa. He also had some tough matches [this week] and hopefully I'll be fresh and I'll give it all."

While Djokovic and Sonego thrashed away into the night, nine-time champion Nadal had no such workload issues on Saturday.

Nadal beat Alexander Zverev on Friday to set up a semi-final against American Reilly Opelka, and the Spaniard snatched a 6-4 6-4 win from that contest to reach the title match.

Novak Djokovic's Internazionali BNL d'Italia quarter-final with Stefanos Tsitsipas was halted by persistent rain on Friday with the world number one a set and a game down.

Reigning champion Djokovic, who is seeking a sixth triumph in Rome, struggled to get going against Tsitsipas and trails 6-4 2-1 ahead of the scheduled resumption of play on Saturday.

The top seed lost serve in the first game and continued to make some uncharacteristic errors that saw him trail 4-1 at one point.

While Djokovic did earn a first break in the sixth game, Tsitsipas stood firm to take the opening set and was in total control when again breaking his opponent early in the next set.

However, soon after the Greek had opened up a 2-1 advantage, the worsening conditions led to a pause in proceedings and organisers were eventually forced to bring the day's play to an end.

Djokovic, who converted just one of his six break point opportunities, will return to the court on Saturday and will need to improve if he is to join Rafael Nadal in the final four.

Nadal exacted some revenge on Alexander Zverev earlier on Friday to reach the semi-finals for a 12th time.

The Spaniard lost to Zverev at the same stage of the Madrid Open seven days ago but responded to questions over his form by easing through this latest encounter.

Nadal, who saved two match points before beating Denis Shapovalov on Thursday, raced 4-0 ahead in the first set against Zverev and had little trouble seeing the job through.

Aiming for a record-extending 10th title in the Italian capital, Nadal saved all eight break points he faced in the second set to advance 6-3 6-4 in two hours.

"I played more solid than Madrid. Conditions are different," he said in his post-match interview. "Here the conditions are a little more normal. I was able to control a little bit more."

"I'm happy. I played a very solid match with not many mistakes, playing the way that I have to. It's an important victory for me against a great player."

Nadal will face Reilly Opelka for a place in the final, the American beating qualifier Federico Delbonis 7-5 7-6 (7-2) to reach his first ATP Masters 1000 semi-final.

Opelka entered the tournament on a six-game losing streak, but he kept his good run going in Rome by earning the only break of the opening set in the 12th game.

Both players held throughout the second set and it was big-serving Opelka who prevailed 7-2 in the tie-break.

The day's other quarter-final between Lorenzo Sonego and Andrey Rublev also fell victim to the bad weather and will get under way on Saturday.

Novak Djokovic cruised into the quarter-finals of the Internazionali d'Italia with a straight-sets demolition of Alejandro Davidovich Fokina on Thursday.

The world number one took just an hour and 10 minutes to wrap up an emphatic 6-2 6-1 victory at the Foro Italico.

Davidovich Fokina broke the top seed's serve in the first game of the match, but that proved to be a false dawn for the Spanish qualifier.

Djokovic put the 21-year-old under huge pressure with another returning masterclass, breaking back immediately and on two more occasions to seal the first set.

The 18-time grand slam champion was relentless in the second set, forcing Davidovich Fokina's unforced error count up to 30 as he breezed into the last eight.

Djokovic, who has reached at least the quarter-final stage in each of his 15 appearances at the prestigious tournament in Rome, was waiting to learn whether he would face Stefanos Tsitsipas or Matteo Berrettini for a place in the semi-finals.

The Serbian said: "I thought I played well. He started well and broke my serve in the first game. I made some errors, but I managed to break back right away and establish the control and consistency on the court.

"I think from the back of the court I was just a bit more solid than him.

"He made some unforced errors and double faults in key moments, which obviously helped me get that necessary break forward.

"I thought I played better, at least 20 or 30 per cent better, than I did against [Taylor] Fritz a few days ago. I am on a good trajectory and hopefully tomorrow will be even better."

Novak Djokovic returned following a rain delay to beat Taylor Fritz in the second round of the Internazionali BNL d'Italia after Felix Auger-Aliassime dumped Diego Schwartzman out.

Djokovic, playing his first match since a shock loss to Aslan Karatsev in the semi-finals of the Serbia Open on home soil, dispatched American Fritz 6-3 7-6 (7-5) on Tuesday.

The world number one, who missed the Madrid Open, won the first three games of the match and saved both break points he faced in the opening set.

Fritz had broken for a second time in the second set to level at 5-5 when the rain came at the Foro Italico, but the top seed was able to come back out on court to finish off the job and will face Cameron Norrie or Alejandro Davidovich Fokina in the third round.

Auger-Aliassime secured the third victory over a top-10 opponent in his fledgling career, beating eighth seed Schwartzman 6-1 6-3 to move into round three.

The 20-year-old Canadian only needed 64 minutes to send the Argentine packing, converting five of the six break-point opportunities he earned.

Matteo Berrettini saw off Nikoloz Basilashvili 4-6 6-2 6-4 in the first round less than 48 hours after the Italian was beaten by Alexander Zverev in the Madrid Open final.

Gael Monfils was unable to win his first match since the Australian Open, as Lorenzo Sonego got the better of the fit-again Frenchman, who had been sidelined with a calf injury, 6-4 5-7 6-4.

Reilly Opelka moved into the last 16 with a 6-4 6-4 defeat of Lorenzo Musetti, while Pablo Carreno Busta's withdrawal due to lower back pain handed Kei Nishikori a walkover.

Daniil Medvedev and David Goffin were unable to start their second-round matches due to the weather in Rome.