“If you saw the ruins it left behind, you’d be pretty confident I won’t take that drug again.”

Last April, a month after reaching a career-high ranking of 41, Britain’s Dan Evans failed a drugs test at an ATP event in Barcelona. He had taken cocaine out of competition four days earlier.

This weekend, the 27-year-old will attempt to qualify for the ATP Challenger Tour event in Glasgow, having been awarded a wildcard by the Lawn Tennis Association on his return from suspension.

Evans is full of regret.

“It’s a shocking drug, and it’s not just in sport – it’s terrible in life. It’s a life-ruiner,” said Evans at the Scotstoun Tennis Centre.

“It’s like drink-driving – everyone knows you shouldn’t drink-drive. I took it. I knew beforehand I shouldn’t have. It’s illegal for one, never mind me being a sportsman.

“It’s the worst thing I’ve ever done. It’s a shocking thing to do, it’s let down many people. Not just that, it’s brought unwanted press to tennis.

“God knows what some of the greats of the game thought when that sort of thing comes into the headlines.”

Evans could have faced a four-year ban but that was reduced by the International Tennis Federation (ITF) because cocaine is not performance-enhancing and it was taken out of competition.

The ITF said Evans “promptly admitted his violation” and it accepted his account that the substance was only still in his system because “leftover” cocaine had accidentally mixed with permitted medication in the “same pocket of his washbag”.

‘There’s been some terrible moments’

Evans says he did not play tennis for eight and a half months, and left his racquet at his parents’ house so he was not haunted by the sight of it.

He returned to training in late February, and says he was “terrible” in a “horrible” first session back.

Evans has passed much of the past year on the golf course, and away from social media. There was a holiday in Marbella, which he says was low-key, but he spent most of the time in Cheltenham with his girlfriend Aleah, sometimes struggling to fill his days.

“I was saying to my girlfriend how long a working day actually is: 9 to 5 is a long, long time,” he said. “Daytime TV is not good.

“It wasn’t easy, there’s some terrible moments in those nine months. At the start I was heartbroken not to be playing tennis.

“There isn’t that much you can do in the day when other people are working.”

Something else Evans found difficult was telling friends and family about his indiscretion.

“It’s just a terrible conversation, whoever it’s with,” he said.

“There’s that many people that support you, even if it’s a text at the end of the match, or they stay up when you’re playing in America and are knackered for work the next day.

“The embarrassment you put your girlfriend’s mum through, her parents, that’s not what they want their daughter round, is it? And then you’ve got your mum at work, or my sister at work.

“It’s not a situation I hope anyone will be in again.”

Evans, who looked to be in good shape in practice on Friday, is without a coach and has not decided on his schedule for the next few weeks.

He will face compatriot Ed Corrie, the world number 427, on Saturday.

Evans is unranked, and admits to many doubts, but believes he can fight his way back into the world’s top 50.

“If my body holds up, I think so, unless the game has considerably moved on in a year,” he said. “Seeing the older guys do well, that was the only thing I was really looking out for when I wasn’t playing.

“I had doubts every day and I still have doubts now, and there will still be doubts until there are two digits next to my name.

“A year’s a long time, especially when I was doing nothing. I probably won’t feel stress like I have in the last year. Winning tennis matches, or losing tennis matches, won’t be such a big deal.”

Evans would not be drawn on whether he had ever taken drugs before last April, but says he has been tested four times since returning to training at the Edgbaston Priory Club in Birmingham.

He has also told his story in two videos, which the LTA will distribute to players as part of its drug education programme.

His wildcard for Glasgow was awarded after he passed a range of physical, medical and nutritional tests set by the LTA.

The organisation’s chief executive, Scott Lloyd, says further support will be forthcoming as long as Evans keeps his side of the bargain.

“If he continues to do that, then we want to help him make that road back to the top of the game,” said Lloyd,

“We have zero tolerance to doping, but what I think Dan has shown us thus far is that he is absolutely willing and trying to do that to the best of his ability.

“He needs to earn his way back into the tour, and I think he wants to demonstrate that, too – I genuinely do.

“This is not about handouts, this is about providing the opportunity.”