![Michael Phelps stretches prior to competing in the men's 100 meter freestyle preliminary, Saturday, April 18, 2015, at the Arena Pro Swim Series in Mesa, Ariz. (AP Photo/Matt York Stock Photo - Alamy Michael Phelps stretches prior to competing in the men's 100 meter freestyle preliminary, Saturday, April 18, 2015, at the Arena Pro Swim Series in Mesa, Ariz. (AP Photo/Matt York Stock Photo - Alamy](https://c8.alamy.com/comp/2N2G63A/michael-phelps-stretches-prior-to-competing-in-the-mens-100-meter-freestyle-preliminary-saturday-april-18-2015-at-the-arena-pro-swim-series-in-mesa-ariz-ap-photomatt-york-2N2G63A.jpg)
Michael Phelps stretches prior to competing in the men's 100 meter freestyle preliminary, Saturday, April 18, 2015, at the Arena Pro Swim Series in Mesa, Ariz. (AP Photo/Matt York Stock Photo - Alamy
![Michael Phelps looks at the scoreboard after competing in a 200-meter freestyle preliminary race at the Arena Grand Prix swim meet, Thursday, April 14, 2016, in Mesa, Ariz. (AP Photo/Matt York Stock Michael Phelps looks at the scoreboard after competing in a 200-meter freestyle preliminary race at the Arena Grand Prix swim meet, Thursday, April 14, 2016, in Mesa, Ariz. (AP Photo/Matt York Stock](https://c8.alamy.com/comp/2MYWEB7/michael-phelps-looks-at-the-scoreboard-after-competing-in-a-200-meter-freestyle-preliminary-race-at-the-arena-grand-prix-swim-meet-thursday-april-14-2016-in-mesa-ariz-ap-photomatt-york-2MYWEB7.jpg)
Michael Phelps looks at the scoreboard after competing in a 200-meter freestyle preliminary race at the Arena Grand Prix swim meet, Thursday, April 14, 2016, in Mesa, Ariz. (AP Photo/Matt York Stock
![Michael Andrew, the youngest US swimming pro ever, meets Michael Phelps, the 2nd youngest, before the Mesa Grand Prix. : r/sports Michael Andrew, the youngest US swimming pro ever, meets Michael Phelps, the 2nd youngest, before the Mesa Grand Prix. : r/sports](https://external-preview.redd.it/WGTzajfn2fEns7Cs9RyV6Z-vizCYAkvNvPqymROGcPs.jpg?auto=webp&s=e76562899cca5a2d233b3799e1cd8f447b6ead4f)
Michael Andrew, the youngest US swimming pro ever, meets Michael Phelps, the 2nd youngest, before the Mesa Grand Prix. : r/sports
![Michael Phelps returns, beats beats Ryan Lochte in 100-meter butterfly final in Mesa - Sports Illustrated Michael Phelps returns, beats beats Ryan Lochte in 100-meter butterfly final in Mesa - Sports Illustrated](https://www.si.com/.image/t_share/MTY4MTg2MzQxOTUyMDcwOTI5/lochte-phelps-mesajpg.jpg)