- London Olympics 2012
Bolt can break 400m world record - Johnson
Michael Johnson believes Usain Bolt can cement his legendary status by stepping up to 400m and has backed the Jamaican to break his world record.
Triple Olympic champion Bolt is considering adding the 4x400m relay to his schedule at London 2012, where he will defend the 100m, 200m and 4x100m titles he won in Beijing.
No athlete has won four gold medals since Carl Lewis at the 1984 Los Angeles Games, and Johnson, who was the first man to win the 200-400 double in Atlanta, has previously warned Bolt that chasing four golds could be costly.
However, Johnson believes Bolt has the talent to break his world record if he decides to step up to the one-lap event.
"He was a 400m runner before he was a 100m and 200m runner," Johnson told ESPN. "He has always been great as a 200m runner but he was a good 400m runner when he was very young.
"He has the build to be a great 400m runner and he certainly has the speed. Without a doubt I think if he chose to make the switch at some point in his career and decided he was going to train for the 400m I am certain he would break the world record and probably run under 43 seconds and become the first person to run 42 seconds."
Although Bolt has expressed his interest in adding the 4x400m relay to his schedule, his coach Glen Mills has expressed his doubt that Bolt will be ready for the one-lap event next summer. But regardless of his decision, Johnson admits Bolt is red-hot favourite to walk away with three Olympic gold medals once again.
"I've heard all types of rumours, whether he is going to run 400m or 4x400m relay, I think obviously best sprinter in the world, he's the best there has ever been," Johnson said. "He is an incredible athlete and I think he will be focused and ready to go next year defend his titles at 100m and 200m which he has said he wants to do and [Jamaica] have the best 4x100m relay in the world at this point.
"Beyond that anything else is just speculation and I think we will just have to wait to see if he decides to do anything else. But I think he is in a great position to repeat  and I wouldn't put my money on anyone else but him for 100m and 200m."