 Less than two weeks after he finished 6th at the 1968 Indianapolis 500, Duman was at the next race of the USAC Championship season, the Rex Mays Classic at Milwaukee.Duman started 14th in the 24-car field, driving the Central Excavating Gerhardt Turbocharged Offy.On the third lap, the cars of Bay Darnell and Norm Brown reportedly got tangled in turn one.