Michael Johnson lost his 200 metres world record to an extraordinary run by new Olympic double sprint champion Usain Bolt on Wednesday and predicted the big Jamaican could now take his 400 mark too.
Johnson, who won the 200m and 400m double at the 1996 Atlanta Games, was as impressed as anyone in the 91,000 capacity Bird's Nest crowd when Bolt shaved two hundredths of a second off his previous 200m world best to win gold again.
"It's incredible. It leaves you speechless but yes, I did [think he would break my record]," the American said.
"He needs to set himself some other goals. He could be world record holder in 100, 200 and 400."
Johnson, now retired from competition, watched Bolt run flat out to the tape to better his 12-year-old record of 19.32 seconds set at the Atlanta Games.
Bolt also broke his own 100m record on Saturday in the Olympic final to become the first man to achieve the Games sprint double with world records.
Johnson had described Bolt as "Superman 2" in an interview for BBC television.
"He finished up in an incredible time. This was an incredible performance, he wanted that record.
"Congratulations Usain Bolt.
"He got an incredible start. I looked at his start and just went wow. It was more amazing than the 100 metres ... Guys that tall should not be able to start like that ...," said Johnson.
"He wanted that record. This is his favourite event, he went for it, he came in focused on it, knowing he would most likely win the gold.
"My concern was he would not have the ability to hold that speed for the entire race but he showed he has been working on that. He used every ounce of energy, he wanted that record."
Following the disqualification of the second and third-placed athletes for running in the wrong lane, US pair Shawn Crawford and Walter Dix took silver and bronze.