Great Britain were beaten 19-9 by Hungary in their opening match at the European Water Polo Championships in Eindhoven.
Team GB took an early lead with a goal from Ciara Gibson-Byrne but failed to capitalise on a number of Hungarian expulsions to increase their advantage and quickly fell behind to trail 4-1 by the end of the first quarter.
Szilvester Fekete's team, who were playing their first competitive match for four months, struggled to match their opponents' physical power and clinical finishing throughout the match and despite a hat-trick from Fiona McCann it was a chastening way to start Olympic year.
Captain Fran Leighton admitted it was a difficult return to the Euros after a 15-year absence.
"There's been a lot of excitement having not been here for so long and it was all positive from the start with the early goal but it was a shame we didn't take our chances," she told BBC Sport.
"I'm sure there were a few nerves around today so hopefully we got them out of the way with two more very tough matches coming up."
Great Britain next face defending champions Russia on Friday before meeting host nation and Olympic Champions Holland on Sunday and Leighton knows both will steepen the learning curve before London 2012.
"If we're going to compete in the Olympics we need to play the top teams and discover what our strengths and weaknesses are and work on them in the next six months," said the 28 year-old.