Six seeds – Pablo Cuevas, Paolo Lorenzi, Gilles Simon, Jan-Lennard Struff, Jiri Vesely and Horacio Zeballos – were all beaten on a dramatic Wednesday at the Generali Open.

Austrian wild card and World No. 157 Sebastian Ofner kept his nerve in a rain-interrupted 6-3, 2-6, 7-6(3) victory over top seed Pablo Cuevas – making his tournament debut – in two hours. The second-round match was suspended due to rain with Ofner serving at 2-5, 15/30 in the second set.

“I’m happy that I stayed focused during the tie-break [and] I played well,” said #NextGenATP’s Ofner. “For sure, the experience in Wimbledon helped me today. It’s a great feeling to be in the quarters and of course it’s very special to play in front of my home crowd.”

Ofner, now 4-1 on the year, will next challenge Renzo Olivo, who defeated fellow Argentinean and eighth seed Horacio Zeballos 7-6(4), 6-2.

Fourth seed Simon lost 6-4, 6-4 to Serbian Dusan Lajovic, who now plays Kitzbühel resident Philipp Kohlschreiber in the last eight. The German recorded his 15th match win at the ATP World Tour 250 tournament, where he won the 2015 title (d. Mathieu), in beating seventh seed Jiri Vesely 6-3, 6-3.

Elsewhere, Thomaz Bellucci ousted sixth seed Struff 6-4, 7-6(3) for a quarter-final clash against second seed Fabio Fognini, the recent Plava Laguna Croatia Open Umag titlist, a 6-4, 6-4 victor over qualifier Miljan Zekic.

Joao Sousa ousted third seed Lorezni 6-7(5), 6-4, 6-1 to reach the quarter-finals, where he will face Gerald Melzer. The Austrian pleased his home crowd with a 6-3, 7-6(1) win over Santiago Giraldo.

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Roger Federer will make his first appearance in Montreal since 2011 at next week’s Coupe Rogers, when he begins his North American summer swing.

The Swiss superstar has not competed in Canada since a 2014 final loss to Jo-Wilfried Tsonga when the ATP World Tour Masters 1000 tournament was held in Toronto.

“I’m happy to be coming back to Montreal, as I have not had the chance to play there for many years,” said Federer. “This 2017 season has been very exciting and I am really looking forward to being back on the court on the ATP Tour.”

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Federer captured two titles in Toronto in 2004 (d. Roddick) and 2006 (d. Gasquet). He also finished as runner-up in the Canada finals of 2007 (l. to Djokovic), 2010 (l. to Murray) and 2014. Overall, he has a 31-9 record at the prestigious tournament.

Closing in on his 36th birthday, on 8 August, Federer has enjoyed a hugely successful 2017 season, compiling a 31-2 match record with five titles – including two Grand Slam championships at the Australian Open and Wimbledon, and two ATP World Tour Masters 1000 crowns at the BNP Paribas Open in Indian Wells and the Miami Open presented by Itau.

His compatriot, Stan Wawrinka, announced on Wednesday that he has withdrawn from the Montreal event and also the Western & Southern Open in Cincinnati – due to a knee injury.

“After much consideration and consultation with my doctors and my team, I have decided to skip Canada and Cincinnati to be on the safe side, although I’ve been battling hard to be fit for these events,” said Wawrinka.

“It’s hugely disappointing for my fans and for myself that I have to make this decision. But I need to be 100 per cent confident before I resume competition that the injury that has plagued at Wimbledon has been resolved. My team and I are doing everything to make this a speedy recovery.”

Wawrinka, who is currently No. 4 in the Emirates ATP Rankings, struggled with knee problems during the grass-court swing at the Aegon Championships and Wimbledon.

Fernando Verdasco is through to the second round of the Abierto Mexicano de Tenis Mifel but not without an almighty scare. The Spanish No. 6 seed saved two match points to deny NextGenATP player Ernesto Escobedo 6-7(6), 7-5, 6-2 on Tuesday.

Escobedo, No. 83 in the Emirates ATP Rankings, channelled his Mexican heritage and had the Los Cabos crowd in his favour as he surged to a 7-6(6), 5-3 lead. The 33-year-old Verdasco then managed to recover from 15/40 – two match points for Escobedo – and reeled off 10 of the last 12 games for victory in two hours and 22 minutes.

It was the second time this season the pair had clashed. Verdasco also won their prior showdown in three sets in the second round of the Miami Open presented by Itau. Unseeded Vincent Millot is next. The Frenchman saw off lucky loser Brydan Klein 6-2, 3-6, 6-1.

Earlier, Millot’s countryman, NextGenATP player qualifier Quentin Halys, upset defending champion Ivo Karlovic 7-6(5), 7-6(8). The 20 year old withstood 12 aces and saved four break points on his way to a second-round meeting with Damir Dzumhur. It marked just Halys’s second ATP World Tour match win after he defeated fellow NextGenATP player Stefan Kozlov first up in Atlanta last week.

American Bjorn Fratangelo posted a 6-4, 6-4 win over Japan’s Tatsuma Ito. He will next face No. 7 seed Adrian Mannarino. Canada’s Peter Polanksy also advanced. His 7-5, 7-6(5) victory over Japan’s Yasutaka Uchiyama booked a second-round clash with Australia’s Thanasi Kokkinakis.

Three-time champion Juan Martin del Potro’s Citi Open winning streak is up to 15 matches with the Argentine taking down Lukas Lacko on Tuesday night. The No. 13 seed downed the Slovak 7-5, 6-2 as he advanced to the third round.

The 28 year old will carry a 5-1 FedEx ATP Head2Head record into a third-round clash with No. 2 seed and 2015 champion Kei Nishikori. The Japanese star narrowly held off Donald Young 6-3, 4-6, 7-6(5).

Lacko’s best chance of snapping del Potro’s winning run came as he broke serve twice to level at 4-4 in the opening set. After he lost a tight opener in 53 minutes, however, the No. 119 in the Emirates ATP Rankings scantly troubled the former World No. 4 again. Del Potro powered through the last five games of the match.

His only loss in Washington, D.C. came as an 18-year-old to Wayne Odesnik in 2007. But this was his first match at the Citi Open since the most recent of this three title runs in 2013.

Nishikori later booked his seventh showdown with the Argentine in a gripping two-hour, 28-minute affair. Young saved match points when he served to stay in the second-round clash – twice at 4-5 in the third set, and once more at 5-6 – before he fought off a further two match points in the deciding-set tie-break.

American Tennys Sandgren landed his maiden ATP World Tour match win with a 7-6(2), 6-3 victory over Japan’s Go Soeda. Sandgren thumped down 10 aces and conceded just two points on his first serve in the opening-round clash. He never faced a break point.

“It feels good. It’s still kind of different being in the main draw on my own ranking,” Sandgren said. “Obviously they’ve got the extended draw here so I feel like I had a small opportunity here to try and win a match or two. I think I played well tonight. Feel like I found some good form so I’m excited about that.”

Australian No. 10 seed Nick Kyrgios is his next opponent. The pair has never faced off.

“That’d be the best player I’ve ever played against, it’s exciting,” Sandgren said. “I hope I bring a good level. I hope the tennis is fun.”

In his first outing as top seed at an ATP World Tour 500 event, Dominic Thiem is comfortably through to the third round of the Citi Open on a soaked Tuesday. A rain-delayed start in the US capital failed to dampen the Austrian’s debut as he powered past Henri Laaksonen 6-3, 6-3.

The 23 year old dropped just one point on his first serve and never faced a break point against the Swiss. It marked his first match since he fell to Tomas Berdych in five sets in the fourth round at Wimbledon.

No. 8 seed Jack Sock advanced to the last 16 for the third straight year after he eked out a narrow 7-6(2), 7-6(6) victory over Romanian Marius Copil. Neither player faced a break point throughout, but it was Sock who proved steadier in the tie-breaks.

The American sealed the win on his second match point when Copil rolled a backhand wide. He will look to make it three straight quarter-finals in Washington when he next meets countryman Jared Donaldson or Australian Marc Polmans.

“He’s a very tricky player. He’s a tough opponent for sure, especially on a court like this,” Sock said.

“It’s a little bit quicker than last week, and he serves cannons. He’s got a great first serve, great second serve … He’s not an easy break at all. I’m definitely happy to get through in straights.”

Russian former World No. 20 Dmitry Tursunov used a protected ranking to make the main draw after ongoing injuries. The 34 year old ground out a 6-4, 6-7(4), 6-4 result over American Mitchell Krueger to set a second-round meeting with No. 11 seed Gilles Muller.

Kyle Edmund was too solid for #NextGenATP player Hyeon Chung, of Korea. The Brit sent down seven aces as he raced through 6-3, 6-1 to set a second-round clash with No. 4 seed Grigor Dimitrov.

Marcos Baghdatis, a former world No. 8 in the Emirates ATP Rankings, also advanced past the first round after he saw off Israeli qualifier Edan Leshem. Neither player managed to break in the opening set before the Cypriot ran away with a  7-6(1), 6-0 result. Ryan Harrison is next.

First coach and most important lesson he taught me
My first coach was my dad, and I think the lesson he definitely instilled in me was hard work. We worked very hard and he said in order to chase your dreams, you definitely have to put in the effort and that’s something that’s really stuck with me throughout my career.

First pinch-me moment on the ATP World Tour
Playing a practice set with Federer in Miami. I had been on the tour for a little bit, and I had seen some of the top guys… I remember I won the practice set, too. I know in hindsight it’s just practice stuff but that was a pretty surreal feeling… That was the year I beat Novak as well (2008). I would have said that but practising with Federer was just a couple days earlier. 

First thing I bought with prize money
I bought my current wife, girlfriend at the time, Kelsey, a trip to Australia (Australian Open, 2009). So that was cool. That was also after my first year so definitely some of my prize money went to that.

First celebrity crush
It’s cliché but just like me and probably everybody else at the time, it was [Anna] Kournikova.

First album I bought?
I think it was the Offspring, “Americana”. That was the “Pretty Fly For a White Guy” CD… Off the album, I think “Staring at the Sun” was my favourite.

First pet
The first pet I had was a little Maltese poodle, her name was Lulu. We got her when I was six. We always laughed because she cost like 60 rand, which is like $8. But I think she passed on some sort of bacterial something to me, because I ended up having my appendix taken out because of her. I don’t want to blame her for it without concrete proof but we ended up laughing about it. The doctor said there was a good chance it might have been from the puppy, so she ended up costing us a little bit more [than $8] but she was great. She was my childhood dog so obviously we had a lot of memories with her.

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