There was at least one man who was not getting carried away by Usain Bolt's scene-stealing turn at Crystal Palace at the weekend. While seasoned onlookers mopped their brows and relocated their dropped jaws, the portly figure at the back of the South London stadium was asked whether the beast of a runner would soon break Michael Johnson's fabled 200 metres world record. “No,” Glen Mills said, matter-of-factly. “He is a long, long way from that.”

Mills is Bolt's coach and has yet to decide whether the Jamaican should run the 100 metres at the Olympics as well as his favoured 200 metres. Everyone wants to see Bolt in the 100 metres - he is the world record-holder - but Mills is being cagey. “I'm under no pressure,” he said. “We've spent four years working on the 200 metres, though.” The implication was he did not want to jeopardise that by bowing to public demand. Bolt, as dutiful a professional as there is in world sport, said that he will happily sacrifice the chance of a gold medal in the 100 if Mills decrees that is the best plan.

The sight of Bolt on his way to a UK allcomers record in the 200 metres was awesome. The man outside him, Wallace Spearmon, the fourth fastest 200 metres runner of all time, was beaten within 30 metres and would have looked more comfortable running away from a pack of rabid greyhounds.

It was a brutally destructive piece of sprinting by Bolt, who eased up in the latter stages to suggest that he could have clipped another two or three tenths off his time of 19.76sec. Johnson's record of 19.32 has never been truly threatened, but Bolt looks capable of a real challenge.

More worrying for British hopes is the prospect of Bolt and Asafa Powell joining the Jamaican 4x100 metres relay team. On Saturday, Britain came third in the relay, behind the United States and Trinidad and Tobago. Britain's time of 38.34 was mediocre in global terms and Marlon Devonish, the sole survivor from the Olympic championship squad of 2004, admitted that the event had moved on.

“We changed the face of it in Athens,” he said. “Other teams analysed what we did and the way we changed our batons. It's not all about flat speed. But the fact is the time we won the Olympics with would have seen us finish fifth at last year's World Championships.”

Devonish recalled that he had an almost telepathic bond with Jason Gardener, Darren Campbell and Mark-Lewis Francis. “I can remember feeling with the boys in 2004 that we just almost knew we were going to win,” Devonish said. “We knew each other for a long time and we were all on the same page.”

Britain's team on Saturday comprised Christian Malcolm, Tyrone Edgar, Devonish and Craig Pickering. Simeon Williamson will probably replace Malcolm in Beijing, but it will take a mighty effort to win a medal.