Lizzie Simmonds won gold in the 200m backstroke on the first day of the Monaco Mare Nostrum in Monte Carlo on Saturday, the first of four medals for Bath-based swimmers.
The British Gas National Centre Bath ace came home in 2mins 10.17secs to finish ahead of Ukraine's Daryna Zevina and Sonnelle Özturk of Germany.
Olympic silver medallist Michael Jamieson won silver in the men's 200m breaststroke, recording a time of 2:12.34. German Marco Koch took gold, while bronze went to Japan's Yasuhiro Koseki.
Jemma Lowe swam a season's best of 58.13 to finish second in the 100m butterfly. Jeanette Ottesen of Denmark won gold and Hungary's Liliana Szilagyi claimed the bronze.
In the 100m backstroke, Chris Walker-Hebborn finished third in a time of 54.61 behind Ryosuke Irie and Junya Koga in a Japanese one-two.
Siobhan-Marie O'Connor clocked 1:58.58 for fifth place in the 200m freestyle and was just outside her season's best with 58.88 on her way to winning the 100m butterfly B final.
