Hannah Miley claimed her second medal of the World Short Course Championships with bronze in the 200m individual medley final.
Miley, 23, who won 400m IM gold on Wednesday, trailed the podium places for much of the race before finishing third behind Ye Shiwen of China and Hungary's Katinka Hosszu.
"I really thought that it was going to be fourth or fifth," Miley said.
"It isn't my strongest event, so I'm really pleased with a bronze medal."
She added: "I've been trying to work on my speed and it worked really well in the Europeans [where she won three medals] and slowly but surely I'm getting there.
"Hopefully some day I'll convert it to long course [50m] because that would be great."
Miley has admitted trying to put on a little more weight to make her "robust" and reiterated her belief that this has been a factor in her post-Olympic improvement in form.
"It's definitely one of the reasons I've been able to keep going a lot more frequently," said Miley, who was fifth in the 400m IM final in London.
Georgia Davies set a new personal best and Welsh record of 26.84 secs en route to qualifying fifth quickest for Sunday's 50m backstroke final.
Compatriot Jemma Lowe, who won 200m butterfly bronze on Wednesday, powered through to Sunday's 100m butterfly final in 57.16 secs.
Lowe is the third-quickest qualifier and admits she is going to need to achieve a time close to her personal best of 56.67 secs to win a second 2012 World Short Course medal.
"I think it's going to take 56-something for a medal so I'm going to give it my best and hopefully I'll be on that podium again," Lowe told BBC Sport.
Francesca Halsall is another medal prospect for Great Britain on the final night in Istanbul, having eased through the semi-finals in the 50m freestyle in 24.49 secs.
In the women's 4x100m relay GB finished eighth.
US five-time Olympic champion Ryan Lochte set his second world record in as many nights, with a 50.71 secs swim in the semi-finals of the 100m IM.
He took five-hundredths of a second off Peter Mankoc's 2009 record but told BBC Sport he had made mistakes and could go quicker in Sunday's final.
"During that race I think I messed up in a couple of places so I know there is time for improvement - we'll see if I can fix that," Lochte said.
Lithuania's Plymouth-based 15-year-old Rute Meilutyte won her second gold of the competition and third medal of the championships with victory in the 100m breaststroke final.
"It's the one I train for so I'm so pleased," said Meilutyte.
"All the girls came back amazingly and I've been practising strong last lengths. I didn't get that right in the morning and I was a bit down about it but I got it right tonight, which is great."