Thornton began his career around 1956 in
Los Altos, California, coaching swimming at
Los Altos High School, where under his direction the team broke 13 national records out of 20, and won four straight Northern CIF titles by 1960. At Foothill, he led his teams to eight national swimming titles, and five state Junior College championships in
water polo.
Outstanding swimmers prior to 1974 Outstanding swimmers coached by Thornton before he began at Berkeley included 1960 and 1964 Olympian
Steve Clark, 100-meter freestyle record holder,
Gary Ilman, a '64 Olympic medalist in the 100 freestyle who swam for Foothill Junior College, and Canadian
Ralph Hutton, a three-time Olympic finalist. Thornton also trained European champions from Sweden, Peter Fiel and Ingmar Ericksson. Australian swimmer and 1972 Olympic triple gold medalist
Shane Gould trained at the Foothill Aquatic Club during High School. The Berkeley team's record in dual meets during his tenure was 231-85. They won
NCAA Championships in 1979 and 1980, and were ranked in the top 10 in national polls in 28 seasons.
Outstanding swimmers coached Outstanding Olympians coached by Thornton included U.S. team member
Peter Rocca, and Swedish Olympic team freestylers
Bengt Baron,
Pelle Holmertz,
Par Arvidsson, and
Thomas Lejdstrom and freestyle sprinter and 1992 Olympic gold medalist
Joel Thomas. He coached Canadian Olympian
Graham Smith. He coached
Duje Draganja, who took silver in the 50-meter free at the 2004 Athens Olympics.
International competition In international competition, Thornton coached United States swimming teams at the
1979 FINA Synchronised Swimming World Cup and the 1981
World University Games. He was a coach for the United States team at the
1992 Summer Olympics and an assistant coach at the
1983 Pan American Games, the
1986 FINA World Championships, the
1991 Pan Pacific Championships, and the
1998 FINA World Championships. He served as president of the
American Swimming Coaches Association and on its board of directors, and was a member of the
NCAA Rules Committee. ==Awards==