Tyson Gay — 9.69 seconds

Tyson Gay's 9.69 seconds in Shanghai 2009 equaled the then-world record and made him the first man to legally break 9.70 seconds in the US. His personal best is the same as #3 Yohan Blake's 9.69, but Gay ran it 2 months earlier, making him historically the second-fastest human. Despite later serving a one-year doping ban that disqualified his 4x100m relay medal, his 9.69s at sea level is faster than the average elite sprinter's lifetime best by 0.18 seconds, and he achieved it at age 27—older than the typical peak age for 100m sprinters (25-26).