At the Euro Meet in Luxembourg, Hungarian World Cup queen Katinka Hosszu clocked 8:37.77 over 800m freestyle to get a 16-event schedule underway at the start off three days of action.
Ukraine's backstroke ace, putting in some winter endurance work, clocked 8:44.40 for second, with Frankfurt's Sarah Koehler third in 8:49.68.
Hosszu was back in within the hour, racing to a 4:41.18 meet mark in the 400m medley ahead of a 4:48.24 for teammate Zsuzsanna Jakabos, before the two returned to the fray for the 200m butterfly, Hosszu the victor once more in 2:11.54 ahead of Lisa Hoepnik, of essen, on 2:14.85, Jakabos 4th in 2:15.32, a touch behind Ulster's Bethany Carson, on 2:15.06. Hosszu raced more than any other swimmer in the world on her way to world cup victory and a $100,000 prize last year.
Yannick Lebherz, of Potsdam, clocked 4:23.66 to win the men's 400m medley ahead of breaststroke ace Marco Koch, of Darmstadt, on 4:31.58.
Sergiy Frolov was the dominant force in the men's 1500m freestyle, winning for Ukraine in 15:21.22. His 16-year-old teammate Mykhailo Romanchuk clocked 15:54.75 for second as the last man inside 16mins.
The 200m butterfly had Denmark's Victor Bromer out front on 2:06.67, ahead of Marius Kusch, of Essen, on 2:08.16, Dan Jones, of Plymouth Leander on 2:09.35 and a rare 'fly appearance for German world titles medallist Christian, Vom Lehn, of Essen, on 2:10.13.