Bailey–Johnson 150-metre race

The Bailey–Johnson 150-metre race was a track and field event that occurred in Toronto, Ontario on Sunday, 1 June 1997. In an effort to settle the dispute regarding who was the world's fastest man, a race not sanctioned by IAAF was held at SkyDome between 1996 Olympic 100 metre champion Donovan Bailey from Canada, and 1996 Olympic 200 metre and 400 metre champion Michael Johnson, from the United States.

The unofficial title of "world's fastest man" typically goes to the Olympic 100 metre champion. The Olympics 100–200 metre double had been achieved only four times before 1996: at Munich and Los Angeles for men and Munich and Seoul for the women.

In 1996, the host of NBC's Olympics coverage Bob Costas, and others, pointed out that Johnson's gold-medal performance in the 200 m (19.32 seconds) was faster than Bailey's 100 m performance (9.84 seconds) in that 19.32 divided by two is 9.66. Bailey later dismissed Costas' comments as "a person who knew nothing about track talking about it with a lot of people listening", nonetheless, the sportscaster's remarks touched a nerve.

The 200 metre time almost always yields a "faster" average speed than a 100 metre race time, since the initial slow speed at the start is spread out over the longer distance. In other words, the second 100 metres is run with a "flying start", without the slow acceleration phase of the first 100 metres and without the greater than 0.10 s reaction time of the start. In fact, each 200 metre gold medalist from 1968, when fully electronic timing was introduced, to 1996 had a "faster" average speed at the Olympics, save one, yet there had been no controversy over the title of "world's fastest man" previously, until Bob Costas' remarks during the 1996 Olympics.

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