The Netherlands' women withstood a late fightback to beat fellow medal contenders Hungary 14-10 on the opening day of the women's European Water Polo Championships in Belgrade as Serbia opened their men's account with a hard-fought victory over Croatia.
The Dutch, silver medallists at both the 2014 European and the 2015 World Championships, were leading from the outset in their Group A encounter against the 2014 bronze medallists, powering into a 10-3 lead midway through the third quarter.
But the Magyar's slowly fought their way back into the contest, benefiting from some sloppy defending to reduce the arrears to 13-8.
It proved too little, too late, however, as the Dutch remained four goals ahead to make a strong start to their bid for a first European crown since 1993.
Yasemin Smit scored six goals for the winners while Dóra Antal and Barbara Bujka managed three each for Hungary.
There were no such tensions for Greece as the 2011 world champions powered to a 27-3 win over Portugal, while three-time former champions Russia thrashed Turkey 29-0.
Defending champions Spain will start their competition tomorrow with a clash against Croatia.
On the men's side, meanwhile, Spain began their bid for a first ever European title with a 13-4 win over Slovakia, easing back after moving 10-2 ahead at the halfway point.
Their foremost Group A rivals Montenegro also won, 13-6 over The Netherlands, while France enjoyed a 17-7 triumph over Malta.
But it was the clash between hosts Serbia and Croatia which created most excitement, with the home side winning 13-6 in front of a Championship record crowd of 11,000.