Stan Wawrinka believes he has what it takes to get back to playing “great tennis” again, the former world number three said after claiming his first victory in 15 months at the Italian Open on Monday.

The 37-year-old Swiss knocked out 14th seed Reilly Opelka 3-6, 7-5, 6-2 in the Rome Masters first round to win for the first time since last year’s Australian Open.

Playing just his third match of the season, the three-time Grand Slam champion rallied from a set and a break down to beat the 6ft 11 inch (2.1 metre) American and set up a second round match with Serbian qualifier Laslo Djere.

Wawrinka missed the majority of the 2021 season dealing with a foot injury that required two surgeries.

His ranking has dropped to 361 in the world and he admits there were moments during his time away from the sport where he felt he was “way too far to be able to come back”.

The desire to end his career on his own terms helped him work hard to rehabilitate his foot.

“After two surgeries, at my age, I could easily stop playing because my career is way better than what I expected when I grew up, when I was young,” Wawrinka said on Monday.

“But I still have this fire on me. I still believe that I can play great tennis. I still believe that I can make some big results, maybe not now, but in few months.”

Meanwhile, Canadian Denis Shapovalov apologised after losing his cool in an argument with chair umpire Richard Haigh during his 7-6(5), 3-6, 6-3 victory over Italian Lorenzo Sonego.

Late in the second set, Shapovalov had a second serve overruled by Haigh and crossed the net to his opponent’s side of the court to show the official the ball mark.

The umpire explained to Shapovalov he would have to give him a code violation – which would result in a point penalty since it was his second of the match – because players are not allowed to cross over the net.

“That’s just the rule,” said the umpire before Shapovalov responded: “No it’s not. It’s stupid.”

When the Italian crowd erupted, booing Shapovalov for the lengthy stoppage in play, the 13th seed aimed a swear word at the fans as he yelled at them to “shut up”.

Shapovalov also tried to get a heckler ejected from the stadium before play resumed.

The Canadian’s second serve was deemed out resulting in a double fault, and he received a point penalty which handed Sonego a break and eventually the second set.

After clinching the decider, Shapovalov apologised to the umpire and later acknowledged he was wrong to cross the net.

“It was the heat of the moment so I got emotional. I apologised after. Obviously it was my mistake. There’s nothing they can do,” Shapovalov said in his post-match press conference.

“I’ll know the rule for next time. I definitely won’t step over the net.”

Thiem getting ‘better and better’

Former US Open champion Dominic Thiem continues his quest for a first victory of the season as he suffered a 6-4, 7-6(5) loss to Italian Fabio Fognini.

Thiem has lost all five matches he has contested since returning in March from a 10-month wrist injury lay off, but he showed progress against Fognini on Monday.

“I’m really frustrated right now obviously,” said Thiem.

“Well, things have improved again since Madrid. That’s good. I looked at the stats after the first set on the big screen. Actually they are getting better and better.”

Earlier in the day, former World No 1 Naomi Osaka withdrew from the tournament citing the Achilles injury she sustained in Madrid last week.

Simona Halep kicked off her Rome campaign with a 6-4, 6-4 victory over French veteran Alize Cornet with the former French Open and Wimbledon champion next meeting Australian Open finalist and number seven seed Danielle Collins.

American teenager Coco Gauff was untroubled in her 6-1, 6-4 triumph over three-time major champion Angelique Kerber, while Olympic champion Belinda Bencic skipped past home favourite Elisabetta Cocciaretto 6-4, 6-2.