 Later that same year, he set a new world record (52.6 seconds) in the 100-meter freestyle at the 1967 Pan American Games.At the 1968 Summer Olympics in Mexico City, Walsh won two gold medals in relay events and a silver medal in individual competition.He won the first of his two gold medals by swimming the anchor leg for the winning U.S. team in the men's 4×100-meter freestyle relay, together with teammates Zac Zorn, Stephen Rerych and Mark Spitz.