Latvian free spirit Ernests Gulbis is revelling in his underdog status at Wimbledon and reckons switching shorts in a toilet break makes him feel like a new man.

The 29-year-old, who owns one of the sport’s most destructive forehands, knows he has the weapons to mix it with big guns – but just needs to get his head in the right place to do it.

Gulbis beat Bosnian 27th seed Damir Dzhumur 2-6, 6-4, 6-3, 1-6, 6-3 in a three-hour second round match on the Court 12 show court on Thursday.

And the 2014 French Open semi-finalist said the critical moment came during a toilet break after the rough fourth set.

“I changed my shorts. They were all wet. I did it in the first match as well,” he said.

“It’s a normal thing. I like to do it. I like to change shirts, socks, because I sweat a lot. You feel at least two kilogrammes lighter.”

But Gulbis does not try to psyche himself up in the bathroom mirror during such breaks.

“What can you say to yourself? You don’t try to think about the past or the future. You just try to be in the next point,” he explained.

Gulbis hit a career-high ranking of 10 in 2014 but is now the world number 138 and had to get into Wimbledon through the qualifiers.

The time was when he would have considered Dzhumur a straightforward opponent.

“I would be really confident going into a match with him because I wouldn’t think I could lose against him. Now I’m 100 spots behind a guy like this,” he said.

“I don’t want to sound arrogant but I have the tools to beat all these guys. I just need to get my head straight and my game back on track and then these wins are coming.”

Thinking in terms for fun

He faces either German fourth seed Alexander Zverev or Taylor Fritz of the United States in Saturday’s third round. Fritz led two sets to one when play was suspended on Thursday.

“I like to play against guys whose serve is coming from higher up. I never played Sascha (Zverev). I think the match-up is good for me,” said Gulbis.

“I know him since he was a young kid because I was practicing with (older brother) Mischa a lot back when I was 18, 19. I played doubles with Mischa, I even went to Australia early once with their family to practice there. So I know the family well.

“Right now I’m always the underdog and I have to get the best out of it.”

A video of Gulbis going to the wrong chair in his first round match and having to be directed towards his own bags, towels and water bottles by his British opponent Jay Clarke went viral.

“How boring is everything that this video exploded?! It’s really nothing special, I just missed the seat,” said Gulbis, who shuns social media.

“I blacked out at that moment.”

Gulbis, the son of a wealthy Latvian investment banker and actress mother, has never been far from the headlines in his colourful career.

The right-hander finds it hard to say that he’s having fun at Wimbledon – though suspects he might be.

“Probably yes but I don’t even think in this category. I don’t think if it’s fun or not. You’re so focused. I wouldn’t say that it’s really fun,” he said.

“Yes, you feel fulfilled, relieved, happy, these joyful moments. Now I go back home with my wife, I lay down on the bed, of course I feel happy,” said the man married to former model Tamara Kopaleyshvili.

“Fun is when you hang out with your friends, have a nice conversation.”