Hot favourite Ye Shiwen left in medley medallists' wake
China's Olympic champion Ye Shiwen finished a shock fourth in the 200m individual medley final in the world championships, while teenager Ruta Meilutyte smashed the world record in the women's 100m breaststroke semi-finals.
The 17-year-old Ye had been the hot favourite for the 200m IM final but finished a full second behind the medallists as Hungary's Katinka Hosszu claimed gold.
Hosszu, 24, won by a considerable margin, clocking 2mins 07.92secs, with Australia's Alicia Coutts second at 1.47 seconds back and Spain's Mireia Belmonte 1.53 behind.
Defending champion Ye finished more than a second behind the medalists. "I'm sure she will get back up there. She's a great swimmer and I'm sure it is really tough to get back after an Olympic gold medal," Hosszu said.
Ye has her next chance at an individual medal in Sunday's 400m IM, in which she set the world record at the Olympics last year in controversial fashion by swimming the last leg faster than Ryan Lochte did when he won the men's Olympic title.
Lithuania's teenage star Meilutyte, who pulled off a shock win in the Olympic 100m breaststroke final last year, punched the water in delight as she took a tenth of a second off the world record in yesterday's final.
"The world record was always a dream for me, but yes, obviously a gold medal at the world championships would be like the cherry on top of the ice cream," said the 16-year-old.
Meilutyte broke the four-year-old mark of 1 minute, 04.45 seconds, set by Jessica Hardy of the US, who will get the chance to reclaim her record in the final.
Swedish teenager Sarah Sjostrom regained her women's 100m butterfly title, while defending champion and world record-holder Dana Vollmer could only take bronze.
Sjostrom, who won the 2009 title aged just 15, hit the wall at 56.53 seconds, ahead of Coutts and Vollmer, America's Olympic champion who set the world record in winning the Olympic crown.
Coutts claimed two silver medals in Monday night's session, leaving her with three silvers in two days after anchoring the Australian team in Sunday's 4x100m freestyle relay.
"It has been a big two days for me and I am really happy because now I have two days off," said Coutts, who won five medals at the Olympics, Australia's best haul in the pool in London.
There was more good news for the Antipodeans as Christian Sprenger gained revenge for his defeat in last year's Olympic final when he won the men's 100m breaststroke gold.
South Africa's Olympic champion Cameron van der Burgh, who edged Sprenger into second in the Olympic final, was second and Brazil's Felipe Lima third.