Francesca Painter-Snell blamed lapses in concentration for Great Britain's second narrow defeat to Russia in the water polo competition.
Centre-back Painter-Snell, who is Team GB's top scorer at the Games, reckons her team-mates "have a habit" of losing to the Russians.
She said: "It's becoming too much of a habit now, losing to Russia by one or two goals. We played them in World League and lost by a goal as well. We went into that game knowing that it wasn't impossible to win.
"We were so determined to beat them, so obviously again we're so frustrated. We seem to be coming within inches of these top teams in the world, but we just don't know how to win yet. We're so close, but we're just not quite there. A lot of it is our lapses in concentration.
"I think we'll play really well for most of the quarter and then our concentration will slip and we'll let in a couple of easy, silly goals within a one or two-minute period, which is frustrating for us because they're capitalising on our mistakes."
Great Britain were knocked out of the competition in their last game - against Spain - so their second game against Russia was to settle the fifth to eighth places.
Asked if it was difficult to get pumped up for the classification games, Painter-Snell said: "After the loss to Spain we were absolutely distraught. But we did pick ourselves up and we came into that match fighting. We were in it the whole way through so I think we gave it a good go but we just lost it again right at the very end.
"Even though our games have all been really close, apart from the Australia game, we've got to come away with a win, so we're going to come out here on Thursday and just be absolutely gunning for it, because we're desperate for that win."
Centre-forward Angie Winstanley-Smith said: "The difference is they've got the habit of beating us, they've got a habit of winning and a habit of medalling at major championships. We've only been at the Europeans once in the past 15 years where we came seventh and they came third.
"It's never difficult to play in front of that crowd. You walk out there and all you want to do is deliver a win for that crowd, it's amazing. It's that special. It really is a once in a lifetime opportunity for us girls. We are going to deliver a win for this crowd on Thursday. We are going to get them that win."