Michael Meyer and Rene Warnes swam in the 400m individual medley heats, while the men’s and women’s medley relay teams were also in the Palau Sant Jordi pool in Barcelona.
The men’s 4x100m medley relay team which featured Darren Murray, Cameron van der Burgh, Chad le Clos and Leith Shankland finished 11th with a time of 3:36.22.
“It’s always a good experience to swim on a team with Olympic champions,” Shankland said.
“Overall it was a good performance, but we need to build on the backstroke and freestyle legs if we want to have any chance of being amongst the world’s best.”
Van der Burgh, who won individual gold and silver in Barcelona, said the relay team was on track.
“At this moment in time we are set right to challenge for a medal in Rio in 2016,” Van der Burgh said.
The United States, Australia and Russia were the fastest qualifiers for Sunday’s final.
The women’s team of Jessica Ashley-Cooper, Tara-Lynn Nicholas, Marne Erasmus and Karin Prinsloo also finished 11th in a time of 4:06.46.
“For me the backstroke leg was a PB [personal best] so I’m very happy,” Ashley-Cooper said.
Meyer’s time of 4:21.17 in the 400m individual medley saw him finish 17th overall.
“It was a bit off my best time, but it was a long wait till this race and the backstroke felt a bit sluggish this morning,” Meyer said.
Americans Chase Kalisz, Tyler Clary and Japan’s Daiya Seto were the three fastest qualifiers for Sunday evening’s final.
Warnes had the 22nd-fastest time in the women’s 400m individual medley, which was her only swim at the championships. Her time of 4:48.11 was a personal best.
“Before the race the coach told me that I should aim for a PB. I am glad that I managed that. I can’t ask for more,” Warnes said.
“The wait was very long, so it was not easy to just hang around and wait for all this time, but all in all it was a great experience.”
The fastest qualifiers for the final were Katinka Hosszu from Hungary, Mireia Belmonte from Spain and China’s Ye Shiwen.