Who was the first sprinter to run under 10 seconds?

Question

Who was the first sprinter to run under 10 seconds?

Answer 1

That was Jim Hines of the United States at the U.S. National Championships in June, 1968 with a hand timed 9.9. He then became the first to run an electronically timed 100m under ten seconds at the 1968 Summer Olympics with a 9.95.

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