FILE - United States' Michael Phelps congratulates Singapore's gold medal winner Joseph Schooling after the men's 100-meter butterfly final during the swimming competitions at the 2016 Summer Olympics, in Rio de Janeiro, Brazil on Aug. 12, 2016. Schooling, who beat Phelps to win Singapore's first and only Olympic gold medal at Rio de Janeiro in 2016, announced his retirement, Tuesday, April 2, 2024. (AP Photo/Lee Jin-man, File)
Singapore's Joseph Schooling announces his retirement from swimming at a press conference in Singapore, Tuesday, April 2, 2024. Schooling, who beat Michael Phelps in the 100-meter butterfly to win Singapore's first and only Olympic gold medal at Rio de Janeiro in 2016, announced his retirement on Tuesday. (AP Photo/Steve J. Moore)
FILE - Singapore's Joseph Schooling shows off his gold medal in the men's 100-meter butterfly medals ceremony during the swimming competitions at the 2016 Summer Olympics, Friday, Aug. 12, 2016, in Rio de Janeiro, Brazil. Schooling, who beat Michael Phelps in the 100-meter butterfly to win Singapore's first and only Olympic gold medal at Rio de Janeiro in 2016, announced his retirement, Tuesday, April 2, 2024. (AP Photo/Michael Sohn, File)
FILE - Singapore's Joseph Schooling, right, is congratulated by United States' Michael Phelps after winning the gold medal in the men's 100-meter butterfly final during the swimming competitions at the 2016 Summer Olympics, Friday, Aug. 12, 2016, in Rio de Janeiro, Brazil. Schooling, who beat Michael Phelps in the 100-meter butterfly to win Singapore's first and only Olympic gold medal at Rio de Janeiro in 2016, announced his retirement, Tuesday, April 2, 2024. (AP Photo/Dmitri Lovetsky, File)
Singapore's Joseph Schooling announces his retirement from swimming at a press conference in Singapore, Tuesday, April 2, 2024. Schooling, who beat Michael Phelps in the 100-meter butterfly to win Singapore's first and only Olympic gold medal at Rio de Janeiro in 2016, announced his retirement on Tuesday. (AP Photo/Steve J. Moore)