John Baylon was a judoka who has competed in the 1988 and 1992 Summer Olympics and a multi-medalist in the Southeast Asian Games. He trained in Judo in Japan at the Kōdōkan where he obtained his Judo black belt. At the 1988 Summer Olympics, he competed in the half-middleweight division and lost to Torsten Bréchôt of East Germany. He competed in the same division at the 1992 Summer Olympics and lost to Krzysztof Kamiński of Poland.
Baylon has won a total of nine gold medals in the Southeast Asian Games, first competing in the regional tournament in the 1980s. His first gold medal in the games was in the 1991 edition which was hosted in Manila. He was the flagbearer of the Philippine Southeast Asian Games delegation in 2007. In 2002, Baylon decided to take up Brazilian jiu-jitsu and obtained his black belt in the discipline from Toshiyuki Wado in 2008. He also won medals in Judo at the World Masters, and Asian Games. In the 2011 edition, he failed to win a gold after he was defeated by Vietnamese judoka, Hai Long To in the 81 kg category semifinal. This led to him announcing his retirement from competitive judo. After his retirement, he went on to become a coach in Brazilian jiu-jitsu and Judo based in Metro Manila.

1988 Summer Olympics, Seoul
1992 Summer Olympics, Barcelona