World 400m s/c champion Melanie Costa set a meet mark of 1:58.50 in the 200m freestyle at the Catalan Open in Spain and then returned to the fray at the end of the session to take the 800m in 8:33.90 ahead of the same podium placers in the 200m.
Britain's medley world champion Hannah Miley clocked 2:00.72 and Claudia Dasca 2:04.32 in the 200m, before the order was reversed, Dasca on 8:45.17, Miley on 8:46.65, ahead of Erika Villaecija, on 8:52.31.
By then, Miley had raced the 200m breaststroke, a 2:30.67 effort granting her second place behind Spain's specialist Marina Garcia, on 2:29.04. Miley also finished second in the 100m backstroke, on 1:04.79, the winner Britain-based Bulgarian Ekaterina Avramova, on 1:03.39.
In other action, Ashwin Wildeboer, of Sabadell, clocked 55.99 to win the 100m backstroke ahead of Miguel Rando, on 56.48, with Brit Charlie Boldison on 57.68.
Former world champion on the comeback trail, France's Alena Popchanka, wife of Sabadell coach Fred Vergnoux, took the 50- 'fly in 27.91. At the other end of the spectrum, the men's 1500m free went to Antonio Arroyo in 15:24.57 in a battle with Marc Sanchez, on 15:41.46.