Tyson Gay followed his season-best 100m time in the US Championships by running the second fastest 200m of all time.
Gay says he is ready to run faster
Gay's sensational time of 19.62 seconds on a wet track is second only to Michael Johnson's extraordinary 19.32s at the Atlanta Olympics.
The time was 0.01s inside the best mark of rival Xavier Carter, who broke down in the 200m semi-finals.
On Saturday Gay destroyed the field in winning the 100m in 9.84s, the fastest time in the world this year.
Running into a headwind of 0.5m per second, Gay won the race by 0.23secs, the largest margin of victory at the championships since 1975.
"I was really hoping to get the world record, but the wind conditions weren't too friendly," said Gay, 24.
Asafa Powell and Justin Gatlin share the world record of 9.77secs.
But Gatlin could be stripped of his time, set in Doha last year, as well as his World and Olympic 100m titles after testing positive for illegal quantities of testosterone in April 2006.
The 25-year-old American, who claims he is innocent of deliberate doping, will face a US Anti-Doping Agency arbitration hearing later this year after admitting a violation in order to reduce a possible eight-year ban.
Jamaican Powell has run 9.77secs three times in his career, equalling the mark for the third time last August.
University student Trindon Holliday finished second behind Gay in Indianapolis, coming home in 10.07secs. Collegiate champion Walter Dix was third in 10.09secs.
"That was basically my PR (personal record) so I know I am ready to run faster," said Gay, who has run wind-assisted times of 9.76 and 9.79secs this year.
Only fellow American and former world record-holder Maurice Greene, who ran 9.82secs at the 2001 World Championships, has run faster into a headwind than Gay.