Merten helped set a new world record of 3:57.2 in the 4×100-meter medley relay as a member of the winning U.S. relay team at the 1967 World University Games on August 31, 1967. The record was broken by an East German relay team a little over two months later. At the University Games, he also gold medals in the 100- and 200-meter breaststroke events.