As Chris Mepham tells his story in the same west London hotel where Ryan Giggs asked to meet him a couple of months ago, it is tempting to wonder how differently his career could have turned out had his mum not persuaded him to have one last crack at academy football, or if the centre‑back for North Greenford reserves had managed to get away from work on time.

Mepham’s journey is about much more than fate, however, and in many ways highlights the huge challenges facing any youngster who sets out to become a professional footballer. Released by Chelsea at 14, rejected by Watford and turned away by Queens Park Rangers after being given some brutal feedback that shattered his confidence, Mepham drifted into Sunday league football before resurfacing at Brentford, where he has made such an impression this season that in January Bournemouth had a bid of £6.5m plus add-ons rejected for a 20-year-old with only 14 appearances to his name.

“I still can’t believe that sort of money was put on the table,” says Mepham, who is expected to make his Wales debut against China on Thursday. “I remember the day before deadline day I was having an afternoon nap and my dad came upstairs and with a smile on his face said: ‘Your agent is on the phone.’ When he told me what Bournemouth had offered, I couldn’t believe it. I’d only made eight league starts. It was so surreal. I just didn’t think that moment would ever come, especially five years ago.”

Back then Mepham was reeling from a series of setbacks that started with Chelsea cutting him loose. Mepham remembers his dad taking the call at home and instantly knowing by his expression that it was bad news. “They said there were people higher in the pecking order, centre-backs like Jake Clarke‑Salter and Fikayo Tomori, and that physically others were more developed than me,” Mepham says. “It was a tough one to take but, in fairness to Chelsea, I also felt others were ahead of me in that last year.”

QPR said: 'We can’t see anything we can work on with you.’ That was very hard to hear

What followed was much harder to accept. “After a six-week trial at Watford they brought me into a meeting at Vicarage Road and said they didn’t feel I was at the level they wanted and that there were quite a few things I could improve on. So that was a big letdown. The other one I had lined up was QPR, and that’s my boyhood team. They had a meeting with me and said: ‘When we come to sign someone, we look at one thing which we might try and develop. But we can’t see anything we can work on with you.’ That was very hard to hear. I remember my dad turned around and said: ‘He was at Chelsea for six years. There must be something there.’”

Mepham was devastated. “My mindset after that was awful; that took a massive chunk out of me. In your head you feel you are never going to get accepted anywhere. So at that point I said to my mum and dad that I wanted to take myself out of academy football. I remember enjoying school matches, which I wasn’t able to do when I was at Chelsea, and playing in a Sunday league, half-accepting that this is all it is going to be.”

Then came a window of opportunity, after a game for North Greenford reserves at Uxbridge. “I wasn’t meant to be playing but the bloke starting in front of me had work commitments,” Mepham recalls. “I had a really good game and when I went into the clubhouse afterwards, a Brentford scout called Shaun O’Connor asked how old I was. I think he was shocked that I was 16 playing in men’s football. He said he wanted me to train with Brentford’s under‑16s. My dad was buzzing but I didn’t really want to do it because of what had happened before. But my mum said: ‘Even if you don’t want to go for yourself, go for me because I wouldn’t be able to live with myself if I didn’t convince you to go.’”

Chris Mepham was rejected by three clubs before he joined Brentford. ‘I didn’t really want to do it because of what had happened before,’ he says. Photograph: TGSPhoto/Rex/Shutterstock

It is a good thing that Mepham listens to his mum. He impressed Brentford enough to be given a two‑year scholarship, eventually progressed to the club’s B team and went on to make his debut in the FA Cup last year. His first start was last September, against Norwich in the Carabao Cup, although Mepham feared the worst when he gave away a penalty after 10 minutes. “I thought that was my big chance wasted.”

Nothing could have been further from the truth, as Dean Smith, Brentford’s manager, explained to Mepham recently when the two reflected on that game. Smith liked the way that Mepham, who models his game on John Stones and is not a dissimilar build to the Manchester City defender, kept trying to get on the ball – something that shone through during a run in the team around the turn of the year that prompted interest from Eddie Howe, Bournemouth’s manager, and Giggs, who had just taken charge of Wales.

“Again, quite surreal that someone like Ryan Giggs wants to have a chat with you, especially in his first week in the job,” says Mepham, who qualifies for Wales through his dad’s parents and has represented the country at under-20 and under-21 level. “He was really complimentary, saying he’s seen a couple of my games and that he’s quite keen in the next couple of years to bring me through.”

Playing for Wales in the China Cup would complete a “crazy” season for Mepham, who gives the impression that he has never looked back from the moment Brentford showed the faith in him that had been so hard to find elsewhere. “Having someone believe in you … you’ll never understand how much that means unless you’ve had knockbacks. So that was the best moment ever.”