The side had a strong first half, going into the break just 7-4 down to the Hungarian side - one of the tournament favourites - but failed to find the net thereafter to eventually lose out by a 16-4 scoreline.
Moments after the match, Sports Mole spoke to Buller to get his reaction and preview tomorrow's classification game against Group B basement side Serbia.
Hi Nick, what are your thoughts on how the game went?
"Hungary is the mecca of water polo, basically. It's an amazing place, water polo is at the top over there - their men's team have won at the Olympics three times in a row up until 2012. We knew it was going to be really tough. In the past for example, our national senior team played the senior team of Hungary two years before the Olympics and they lost 25-4. That sort of reflects the difference we can expect when we normally play Hungary. They've been full-time professionals for a number of years as well. So for our girls to go to 7-4 at half time is absolutely amazing. We're over the moon with that.
"Of course this wasn't our final, we've got a big game tomorrow against Serbia. So I had to keep players fresh. I did lots of subbing in the second half and maybe that affected the continuity of the team. The priority wasn't getting the result today, it was preparing for tomorrow. But we're over the moon with the performance in the first two quarters."
You say you expected to lose but as far as the magnitude of the defeat went, did you have a goal difference target in mind?
"As I said, we're pleased that we're making inroads. The under-19 team, when they played the top teams last year, the best difference they managed was 19 goals. In our first game against Greece, it was 18 goals, in our second against the Netherlands it was 13, so a fantastic first two quarters here. We're going forwards, learning every single game and I'm really proud of their effort today."
There was one point in the second quarter where it was 5-4. Did you dare to dream at that point?
"I was aware that the strategy wasn't about winning that game today. We needed to keep people fresh for tomorrow. So I wasn't focused on that. But it can give confidence because there's a huge gulf between Hungarian water polo and British water polo. This is our girls' first step on their journey, and if they're getting results like this on their first step, then with more investment and more opportunity and they can really achieve something."
You mentioned the other day that these top teams are training twice a day whereas you can only train twice a week. Is a tournament like this in some ways bittersweet? On one hand you're losing, which isn't nice, but on the other you are getting the daily rhythm that you want.
"It inspires us. We lost 7-4 the first half, and we're saying if we can do that, let's find a way to get more training, more opportunities, because we can compete with them. There's a player from my club who played professionally in Hungary last year and she told me that the difference is unbelievable. Our girls have been prioritising their school exams, but over there, there was no way that the girls with exams could miss training. It's completely different, with the opportunities. But this will inspire us to believe in ourselves, to believe in this group of players and we'll go forward from here."
Looking ahead to Serbia tomorrow, what sort of a game can we expect?
"A really difficult game for us. Really difficult. They've got some outstanding shooters. They've got some big girls at centre-forward. It will be a very, very hard game."