RIO DE JANEIRO, BRAZIL - AUGUST 11: Michael Phelps of the United States competes in the first Semifinal of the Men's 100m Butterfly on Day 6 of the Rio 2016 Olympic Games at the Olympic Aquatics Stadium on August 11, 2016 in Rio de Janeiro, Brazil. (Photo by Christian Petersen/Getty Images)
RIO DE JANEIRO, BRAZIL - AUGUST 11: Michael Phelps of the United States reacts in the first Semifinal of the Men's 100m Butterfly on Day 6 of the Rio 2016 Olympic Games at the Olympic Aquatics Stadium on August 11, 2016 in Rio de Janeiro, Brazil. (Photo by Mike Ehrmann/Getty Images)
RIO DE JANEIRO, BRAZIL - AUGUST 11: Michael Phelps of the United States reacts in the first Semifinal of the Men's 100m Butterfly on Day 6 of the Rio 2016 Olympic Games at the Olympic Aquatics Stadium on August 11, 2016 in Rio de Janeiro, Brazil. (Photo by Clive Rose/Getty Images)
RIO DE JANEIRO, BRAZIL - AUGUST 11: Michael Phelps of the United States competes Men's 100m Butterfly heat on Day 6 of the Rio 2016 Olympic Games at the Olympic Aquatics Stadium on August 11, 2016 in Rio de Janeiro, Brazil. (Photo by Elsa/Getty Images)
RIO DE JANEIRO, BRAZIL - AUGUST 11: Michael Phelps of the United States competes in the first Semifinal of the Men's 100m Butterfly on Day 6 of the Rio 2016 Olympic Games at the Olympic Aquatics Stadium on August 11, 2016 in Rio de Janeiro, Brazil. (Photo by Adam Pretty/Getty Images)
