Former champion Stan Wawrinka shrugged off his 38 years to reach the French Open second round on Monday, winning a five-set marathon against Albert Ramos-Vinolas which stretched to four hours and 35 minutes and said: "It's why I keep playing".

Wawrinka, ranked 89 in the world, came through 7-6 (7/5), 6-4, 6-7 (2/7), 1-6, 6-4 and will next face Australia's world number 108 Thanasi Kokkinakis after winning a match at Roland Garros for the first time since 2020.

Playing out on the semi-sunken Court 14 arena, the Swiss veteran fired 76 winners and committed 79 unforced errors in an all-out attacking performance which brought back memories of his 2015 title triumph in Paris.

"It's one of the big reasons why I keep playing is to relive those emotions," said Wawrinka.

"I think it was special today again to be here, a lot of support, a lot of fans here. It helped me a lot to stay in the match and to keep fighting for it.

"I always try to make it special, try to have a connection with the people, with the fans, because as I say, it's one of the main reasons why I keep playing and I want to enjoy it as much as possible."

With 14-time champion Rafael Nadal sidelined from the tournament for the first time since 2004 through injury, Wawrinka is one of only two champions in the draw – the other is Novak Djokovic, the title winner in 2016 and 2021.

"I won here many years ago, a long time ago. I was much younger and playing different tennis," said Wawrinka.

"But it's always going to be special to be back here and always have that memory about 2015."

Wawrinka, a three-time major winner, has been battling a series of knee injuries in recent years.

The former world number three missed four successive majors after the 2021 Australian Open before returning in Paris last year.

However, he was defeated in the first round at the French Open and then at Wimbledon, the US Open and this year's Australian Open.

Wawrinka and Kokkinakis, a player who has waged his own injury battles in recent years, have never met.

"When he's healthy, like he's been this year, he's always a dangerous player," said Wawrinka