“I struggle with the weight”. Those were the prophetic words of Birmingham boxer Frankie Gavin when he spoke to Richard McComb at his final training session in the city before setting off for the Olympics. Yesterday Frankie was returning from Beijing, his Games’ dream in tatters after failing to make the lightweight limit.

Hall Green Boxing Club is an anonymous, white, industrial shell of a building, clad with blue metal. When it comes to razzamataz, this place punches well below its weight.

The car park is surrounded by a formidable security fence and the neighbouring shops have razor wire strung along their back walls. Weeds poke up through the cracked concrete, gasping for life.

A sign, hanging on rusting metal gates, carries an uncompromising warning: “Danger! Keep Out.”

The gym is on Olton Boulevard West, which arrows its way through the heart of Tyseley. It is a million miles from the Las Vegas Strip, but if anyone can make it to the boxing capital of the world, and leave it undefeated, Frankie Gavin can. This boy can go the distance.

Gavin is the reigning Commonwealth and World lightweight champion, and, until yesterday, had hoped to pull off a remarkable hat-trick by punching his way to gold in the Olympic Games.

The pressure sits easily on the not inconsiderable shoulders of this 22-year-old super athlete. Gavin, a proven world-beater, is viewed as an exceptional talent, and here’s why.

When he took the World Amateur Championship gold medal in Chicago last November, “Funtime” Frankie – so-called because of his love of practical jokes – became the first Englishman ever to do so. The same year, he was named the British Olympic Association’s boxing athlete of year and the Amateur Boxing Association of England’s senior boxer of 2007.

Boxing aficionados talk of Gavin as a “once in a lifetime” fighter and his sublime skills have attracted the interest of the very biggest names in the sport’s hyperbolic promotion game, including Frank Warren and Oscar de la Hoya.

Much has been made of the fact the Brummie fighter sparred with silver medal winner Amir Khan before the last Olympics, but Gavin, who is publicly shy and self-effacing, does not need to live in anyone’s shadow. He is his own man and stands on the brink of international stardom.

We arrange to meet days before Gavin joins up with his team-mates and heads to the Far East. He is happy to have me along to watch his final day of training in his home city. In boxing parlance, it’s countdown time to Gavin’s date with destiny.

The boxer arrives in a turbo-powered convertible with long-time trainer and confidante Tom Chaney. Springing out of the car, he spots three lads, flabby-waisted and sucking lollies, as they shuffle up the street.

They are mates of Gavin – most people know him around here – and they shout out some earthy greetings. Pointing to the gym, Gavin shouts back: “Come and run and lose some weight if you want.”

The reply is unanimous, and good natured. “F*** you!” Gavin smiles, waves and bobs inside. World champ or not, they don’t allow you to get too big for your boots, or gloves, round here.

Earlier in the car, the temperature gauge hit 80F and inside the gym the air is stifling. The aroma is of blood, sweat and tears. I feel myself perspiring just standing there. Gavin likes it when the mercury rises. He is wearing a synthetic tracksuit designed for broiling. And then he pulls on a second tracksuit, and a sweat top. Then he rams a woolly hat over his head, down to his eyes.

Gavin hops on to a running machine, flips a switch, and is off and running, pounding the revolving tread. “You can talk to me while I run,” he says, setting off on the first 20 minute session of a gruelling afternoon workout. I swear he doesn’t catch his breath, not once.

The boxer has been up since 6.15am, woken by his coach. “I’ve got an alarm clock. It’s called Tom,” says Gavin.

He has been staying at Tom’s home in Hollywood (the south Birmingham suburb, not the LA district) during the run-up to Beijing. Every morning, he hits the streets at 7am for an hour’s run, covering about five miles. Breakfast consists of a meagre bowl of porridge and a supplement drink.

Then it’s back to bed – “Sleep deprivation is a killer for boxers,” says Tom. It is only after this one-hour, 10-minute session of stretching, pummelling and running that Gavin eats his main meal of the day back at Tom’s.

It’s the same every day: steamed chicken, mash spuds, broccoli, and his one concession to luxury, mushy peas and a dash of tomato ketchup. He drinks about six litres of water a day.

Training resumes at 6pm back at Hall Green gym, where Gavin has been based for six years. There is more work on the running machine, four two-minute rounds on the pads, skipping, 15-minute circuit training, and stretching. The programme is relentless, absolutely relentless.

Then it’s time for dinner, and what a treat is in store: a strawberry-flavoured supplement drink. And that’s it. Admittedly, it is sponsored by Ricky “The Hitman” Hatton, but it is still only a strawberry drink, made with water, not milk. Lights out is at 10pm. Gavin is big for a lightweight and his 5ft 8in build is both his greatest asset and his biggest hindrance. To make the division, he has to come in at 60kg (9 stone 6lb).

“I struggle with the weight,” says Gavin, who speaks with a soft Brummie/Irish twang. (His mother, Mary, is from Tipperary. Which sounds like a limerick but isn’t.)

“But when I get down, I’m big for my weight compared to the other fighters because of my build.”

His hands, though, the tools of his brutal trade, are tiny, delicate even. He’s almost apologetic when he shows them to me, clenching and unclenching his fists. “They’re small, aren’t they?” he says, like a bashful schoolboy.

Small, yes. But bloody hell, they pack some power and they are demonically fast.

After the running machine, Gavin dons some gloves, squares up to a punch bag and beats merry hell out of it for six two-minute rounds.

He likes to counter-punch and is a southpaw, so he leads with his left. But it is not just the speed of his steely fists that marks Gavin out. The movement of his feet is mesmerising, too. Dance like a butterfly ...

“His boxing brain is phenomenal, the way he works,” says Tom, as he watches Gavin pile into another punch bag. Frankie is very smart. He will adapt a fight to the way he wants to fight. He’s very elusive. Some people go through their careers with three punches. Frankie has got nine, 10 or 11 really good punches. It is down to the footwork. I would say he has got the best footwork in amateur boxing. You could make a training film out of the way he moves for young boxers.”

Gavin, who was born a few miles away in Marston Green, took up boxing when he was 12. He was invited along to a gym in Small Heath by a neighbour and loved the experience.

“It was something different from hanging around on street corners. My family thought the same,” says Gavin, a former pupil at Archbishop Ilsley Catholic Technology College. He says he goes back to the school for presentations. “I spend more time there now than I did when I was meant to be there,” he adds, smiling.

It was at school that Gavin developed the mischievous tricks that have earned him his nickname Funtime Frankie. He is renowned for playing pranks.

Gavin hooked up with Tom when he was 14. The coach remembers him as being fearless, volunteering to spar with anyone. Most kids, Tom explains, like the idea of boxing, dressing up in the kit and doing the bag work. But they conjure up all kinds of excuses to avoid stepping over the ropes – and getting hurt.

“Frankie would spar every time. Even after he’d finished, if he was walking out of the gym and someone new was arriving, he would turn round, come back, and see if he could spar with them,” says Tom.

“He did some serious, serious training as a kid. He never missed a session. He was never late.”

Such success requires sacrifices all round. Tom has three sons and during Gavin’s pre-Olympic stay they have had to eat when he is out training. It wouldn’t be fair for the boxer to see them gorging on calories, argues Tom.

“All the crap’s been cleared out of the house. There’s no chocolate or crisps. The boys have to eat upstairs,” says Tom. His house, he says, is a wreck, strewn with Gavin’s training gear, kit and a never-ending cycle of washing.

Tom works, fittingly, in the demolition business, and pays glowing tribute to his bosses at the Birmingham-based Armoury Group for allowing him time off to get Gavin ready for Beijing.

Ominously for the opposition – ironically now given yesterday’s developments – Gavin is in the form of his life and says he feels better, fitter, and stronger than he did before the world championships.

He went up a weight, to light welterweight, for June’s European Union Championships in Poland, and took gold, as well as being named best boxer of the tournament.

He did the same thing before he won in Chicago, moving up a division for a run of matches, before going down to lightweight and being crowned world champ.

He soon came to terms with the title.

“I take everything as it comes,” he says. “It was a shock at first and took a while to sink in. But as soon as I get into another tournament, I forget about what has gone before. I just concentrate on that. They say you are only as good as your last fight. I haven’t lost for a couple of years now.”

Gavin’s career record reads 128 fights, with 20 defeats. “Most of those were when I was younger,” he quickly points out.

“I get a little bit nervous when I get to an arena. Not nervous about the opposition, but of losing. But when I walk to the ring, the confidence comes. I feel that no one can beat me.”

Olympic glory may have disappeared for now but 2008 is still set to be a landmark year for Gavin, who will become a father for the first time in December.

He and his 19-year-old girlfriend, Ria O’Shea, who he met at the St Patrick’s Day parade in Birmingham, have just found out they are having a son.