Michael Johnson: "I can go faster"

The 31-year-old American clocked 43.18 seconds to carve 0.11 secs off the record set by his fellow countryman Butch Reynolds in Zurich 11 years ago.

He powered ahead in the second half of the race, leaving the other competitors trailing in his wake. His winning margin was over one second.

As he crossed the line and saw his time Johnson shouted "Yeah" and raised his index finger, telling the world he was number one.

Johnson's win makes him the first man ever to hold both the 200m and 400m world records. It also ties him with Carl Lewis for the most career gold medals at the world championships. Both men have eight apiece.

British hopes dashed

Johnson receives a $100,000 bonus for breaking the record

"It hasn't sunk in yet," said Johnson, who receives a $100,000 bonus from breaking the record along with the $60,000 for the gold medal.

"I am very proud of myself. I could have broken 43 seconds but there was no point in pushing. I just wanted to make sure I did not panic in the final curve. I've always messed up when I am in as good a shape as I am now."

But British men's medal hopes were dashed, with Mark Richardson coming in sixth in 44.65 seconds and Jamie Baulch, the world indoor champion, last in 45.18 seconds.

Brazil's Claro Sanderlei Parrela broke the South American record to win silver in 44.29 seconds, with Alejandro Cardena setting a Mexican record for the bronze with 44.31.

Last season

American Jerome Young, who had vowed that it was his time to finally beat Johnson, could only manage fourth place.

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Johnson had warned before the final that he aimed to break the world record.

"It's been my goal all season," he said.

But the sprinter later hinted that next year could be his last season.

"This was the last thing I had to do," said Johnson. "I will be back next year but after that I know my time will come to quit."