World Champion Phillips was once a timid teenager says his ex-coach

Idowu's winning jump of 17.73 metres in Berlin, a personal best, was too good for Portugal's Nelson Evora, who beat him in Beijing, and he became Britain's first male athletics World Champion for eight years.

Idowu's former coach John Powell spotted him at a schools competition when he was 15 and realised the lanky youth from a Hackney council estate was something special.

He went on to train the Belgrave Harrier for three years but said it was pot luck whether Idowu, who was also a talented basketball and American football player, would show up.

Mr Powell, 50, said: "I'm pretty robust when it comes to persuading teenagers to get to training but he was a difficult one. He often wouldn't show - particularly in the winter because he didn't like the cold.

"But it would have been a crime to waste his natural talent and I wanted to get the best out of him."

Idowu, 30, has told how he was forced to jump over a fence to train for free at the Mile End athletics stadium after school because his family could not afford the £2 admission charge.

He also attended Mr Powell's training sessions at the Crystal Palace National Sports Centre.

Mr Powell, a Met police superintendent in his day job, said: "Phillips was a very independent kid. He used to bring himself to training and I never met his family in the three years I coached him. He was so unassuming and quite timid. "The extrovert we see on television now is the complete opposite to the teenager I knew. There was no dyed hair or piercings. I've no idea where all that came from.

"Phillips was a good kid. He had values. But he was a bit laid back and sometimes lazy because he had the talent and he knew it. The intense focus came later."

Idowu has often been criticised as the nearly-man of British athletics but his gold at the World Championships in Berlin last night helped erase the heartache of being pipped to Olympic glory last year.

Mr Powell said: "I'm delighted for him. It's been a long time coming. I have been managing and coaching athletics since 1976 so I've seen a few go from rags to riches.

"But the fact that Phillips wound up on the top of that rostrum - what an example he is to youngsters around the country. No one can say he had it easy. He came from the back streets of Hackney and made it to the very top."

Idowu's former PE teacher Humphrey Long, who introduced him to the hop, skip and jump as a 12-year-old at Raine's Foundation School in Bethnal Green, said the schoolboy's natural ability had "changed his life".

He said: "I remember the first time I saw him that May afternoon at the Mile End stadium lined up with the other young kids. Most of them didn't know how to hop but Phillips took to it immediately and he loved it so much it became his be all and end all.

"He was a black lad from a poor estate where a lot of other boys ended up involved in crime, so he was fortunate that he went to a school where athletics was very much on the curriculum. It changed his life for ever."

Mr Long, 76, said he "jumped for joy" as he watched Idowu's win on television from his home in Romford, Essex. He said: "Phillips has worked so hard to get where he is and he really deserves a gold medal to show for it."