American Gary Hall has defended his Olympic 50m freestyle title in a hotly-contested race in Athens.
The 29-year-old from Cincinnati touched the wall first in 21.93 seconds ahead of Croatia's Duje Draganja.
South African Roland Mark Schoeman went into the race as favourite after dipping under 22 seconds in the semi-finals but he could only take bronze.
"I'm very proud and very humbled at the same time," Hall told BBC Radio Five Live. "I didn't really expect this."
Hall, who shared the title with American Anthony Ervin, won his second straight title by just one-hundredth of a second.
The 29-year-old was dropped from the United States relay teams and was pleased to have regained his form when it counted.
"Five years ago I was diagnosed with diabetes and told my career is over, so this is special," added Hall.
"Right now, I'm out here having fun and swimming fast."