The British Olympic Association (BOA) confirmed in March that both the men’s and women’s teams had met its criteria and would be allowed to take up the berths allocated to the host nation by world governing body Fina.
Reaching the European finals, to be held in the Dutch city of Eindhoven in January, for the first time in 15 years is a sign of the progress the sport is making in Britain.
“I lost to Ukraine in 2004 in one of my first senior tournaments,” said Winstanley-Smith, 26, who top-scored for GB in Saturday’s victory and skippered the side in the absence of usual captain Leighton.
“In the last six years we’ve managed to get better than them and now beat them by a comfortable scoreline.
“We went to Ukraine in February and won 11-7 there. Today was more emphatic and it shows we’re improving.”
Water polo lost more than half of its funding, external in a round of cuts by UK Sport early in 2009, but has since had some of that cash restored.
Two wins against Ukraine and one against Israel have proved enough to see them through their Euro qualifying group behind Spain, with a dead rubber away to Israel on 15 October still to play.