Duhamel, from Lively, Ont,. and Radford, from Balmertown, Ont., scored a season's best 77.01, putting them behind German pair Aliona Savchenko and Robin Szolkowy who led with a score of 79.02.
Ksenia Stolbova and Fedor Klimov placed third with 76.15.
Kirsten Moore-Towers, from St. Catharines, Ont., and Dylan Moscovitch, from Waterloo, Ont., placed sixth with a score of 69.31.
Paige Lawrence of Kennedy, Sask., and Rudi Swiegers of Kipling, Sask., scored 59.84 for 12th.
The top 16 pairs qualified for Wednesday's free program (10:30 p.m. ET, CBCSports.ca).