Freddie Roach, the bespectacled proprietor of the Wild Card Boxing Club in Hollywood, Calif., and boxing’s best trainer, was emphatic in his appraisal. “He’s maturing more and more, he can follow the game plan now and he’ll be my next world champion for sure, no doubt about that.” Amir Khan had just exorcised the ghost of Marco Antonio Barrera in five bloody rounds at the MEN Arena in Manchester, England , and the energy and pride felt by teacher and student was understandable.

Khan was only six months removed from his brutal defeat in 54 seconds by Colombian Breidis Prescott. Oblivious then to the unique rhythms and narrative of a fight – despite having served a three-year apprenticeship as a pro after winning a silver medal as a 17-year-old amateur at the 2004 Olympic Games in Athens – Khan learned much in the embryonic stages of his relationship with Roach and he has continued to grow and develop in the intervening months.

“Amir has made real progress since we began working together shortly after his fight with Prescott – whom he should never have been in the ring with at that stage in his career, by the way – and he’s a vastly improved fighter,” Roach declared after a public workout by Khan in Manchester to drum up interest in his WBA light welterweight title challenge against Andreas Kotelnik on Saturday, also at the MEN Arena. “He’s willing to learn and he’s a natural athlete, a great athlete, so the work we do in the gym is no problem to him. He loves working. He had worked with me for 10 days when I put him in with Manny Pacquiao on the first day of sparring. I wanted him to get back in the ring with the best. Some people questioned my decision and said he’d get knocked out. ‘If he does, he will get sent home,’ I replied. He didn’t. He performed the way I expected him to perform.

“I wanted to put him right back on that horse. I didn’t want him to be discouraged and he was able to see how well he did with Manny. Amir got the best of him that day and it helped him quite a bit. He and Pacquiao have worked together quite a bit and Amir has picked up a lot. When they spar some days Amir gets the best of him but then some days it’s Pacquiao. He has great potential but I needed to see him pass the test with me and he passed. I see big things for Amir and, if we pick the right fights at the right time, he will go a long way. There is no question in my mind.”

Until he embarked on this crash course in the subtleties of his trade, Khan managed to get by on talent alone. His deficiencies were blatantly apparent. Through 18 bouts, he remained unbeaten, displaying fluid movement, formidable hand speed and considerable power, too, as his record of 15 stoppages suggested. But after he had to climb off the floor to overcome Michael Gomez in June 2008 – three months before he fought Prescott - I found myself writing that “the prodigy has flaws and, if they continue to be unaddressed, they will be his undoing.”

Even in a dominating performance in his previous bout against light-punching Dane Martin Kristjansen at the Bolton Arena he betrayed a worrying vulnerability to being hit by right hands over the top of his low left. Willie Limond, another ostensibly light hitter, induced the most serious crisis of his career by flooring him in the sixth round of their 2007 contest with the same weapon. Gomez, who changed his name from Armstrong in homage to Wilfredo Gomez, the excellent Puerto Rican former world champion, was part of a group of Manchester-based fighters, including Ricky Hatton, Michael Brodie and Anthony Farnell, who came to prominence at the turn of the decade. There was even cause to consider him to be the prospect with the greatest potential, albeit briefly before a reckless lifestyle sapped his stamina. A heavy drinker, he was once charged with murder after a gang fight outside a Manchester nightclub culminated in the victim of his flying fists dropping dead in the street. Ultimately, a judge ruled that he acted in self defense.

Five years earlier Gomez retained enough of his one-time potent punching power to stop another prospect, Alex Arthur, in a barnstorming British fight of the year. But in turning his back on Peter McDonagh and quitting in the fifth round of a scheduled 12-rounder at the National Stadium in Dublin in 2006, Gomez demonstrated again the psychological frailty which had frequently undermined his talent. Khan ought not to have been too inconvenienced by a washed-up veteran who had lost eight out of 43 fights, yet when he got caught with a left hook to the jaw early in the second round the hint of a shock hung ominously in the air.

“Gomez showed throughout his career that he’s a tough fighter with a lot heart and he showed it again when we fought, but I’m much savvier now than I was this time last year – I’m a different fighter since I started to work with Freddie,” Khan said. “I always believed that I had the ability to beat anyone in the world but you need the right team around to bring the best out of you and, for me, Freddie is the perfect guy to have in my corner. I’m the type of guy who sees my coach as a second father but, with Freddie, it’s easy to think like this because he cares about you, he wants you to learn and he works hard so that you do.

“Moving my training camp to California was the best move of my career and, if it took a knockout loss to convince me to come here, I’m happy to live with that because I’m learning something new every day. I remember when I first sparred with Manny I got my respect in the gym because I did well. In the Wild Card you have to treat sparring like a fight because that's what Freddie tells you to do. If the other guy knocks you down, make sure you put him down. Freddie had bets of $1,000 for me to knock Manny down and he said whoever knocks Amir down will get $1,000. For the sparring partners, this is their living. It’s the kind of environment that can either make you or break you as a fighter and being there has been the making of me.”

The hallmarks of Andreas Kotelnik’s unsung career have been fast combinations, solid defensive skills and a well-honed counter-punching technique. A silver medalist at the 2000 Olympic Games in Sydney, where he was beaten by Cuban great Mario Kindelan, the 31-year-old Hamburg-based Ukrainian’s only defeats in 34 fights came on points against Britain’s formerWBC light welterweight titleholder Junior Witter – two judges gave Witter the nod by a single point at the Ice Arena in Nottingham, England - and Frenchman Souleymane M’baye in a bout which most observers thought Kotelnik won. He has never been knocked down as an amateur or pro.

Kotelnik is not a devastating puncher in the mould of Prescott. Since engaging in his first 12-rounder six years ago, he has stopped just five of his last 20 opponents. It was the accuracy and accumulation of his punching that accounted for Wales’ Gavin Rees, from whom he won the WBA belt in March 2008. Rees’ work rate and commitment, along with a concentrated body attack, kept him in the fight until the final stages but the more eye-catching and damaging work was performed by Kotelnik. He punished Rees with heavy right hands to the head almost with impunity, and when the Welshman was saved mercifully in the 12th round by the referee it was no surprise. “You’ve got to get the big shots going, big, big shots,” Rees’ trainer, Enzo Calzaghe, urged before the cruel climax but the fighter knew the score. “I’ve hit him with the big shots,” Rees replied and laughed, an expression of gallows humor, which conveyed the extent of his ordeal.

Khan is a cut above Rees and victory on Saturday could pave the way for a fascinating contest with former world light welterweight champion Ricky Hatton. The Hitman from Manchester was annihilated in two rounds by Pacquaio in May but murmurings suggest that he wants to engage in a farewell fight and what could be better than an all-British encounter with Khan?

“Let’s see if Amir gets the belt first,” said Khan’s promoter, Frank Warren, who worked with Hatton up until his championship-winning bout against Kostya Tszyu in 2005. “It would be a great fight. Personally, I think Ricky Hatton should retire but, if he wants to fight, then why not? I think Khan would beat Hatton. He is the man of his time but he’s got to get through Kotelnik first. That’s the most important thing.”

Roach wants Khan to exploit assets such as speed and the fundamentals, which have worked well in the previous two tests of their alliance (Khan stopped an outclassed Oisin Fagan in two rounds before he beat Barrera). “Kotelnik is always resetting his feet, so if you use lateral movement, he won’t be able to cope and this is one of Amir’s great strengths,” Roach said.

His fighter has the message. “Kotelnik is a fighter who keeps his guard very high, so I think the body shots are going to work as well as the angles. I’ve got to hit and move,” Khan said. “In and out movement is also going to work but he’s a counter puncher, so I have to be one step ahead of him all the time. Kotelnik is a tough fighter and he knows what I’m good at doing, so we worked on changing a few things during camp and I’m ready for the fight now. The key to victory is being patient and using my brain. I have to be careful not to repeat the mistakes that I’ve made in the past.”

Kotelnik believes that same flaws might still be there. “Amir Khan has been doing a lot of talking but I’m not too worried about some boy who got knocked out in one round less than a year ago,” he warned. But if the lessons have been truly learned, Khan should be far more formidable, much more resilient and just too good. It is time for boxing’s one-time best prospect to graduate – thanks to the professor in his corner.

Brian Doogan covers boxing for the Times of London