Budapest (AFP) - David Popovici took a lap to shake some of the gold dust out of his limbs on Tuesday, but then the 17-year-old surged through the field in 100m freestyle qualifying at the World Championships in Budapest.
The night before, Popovici broke the world junior record as he scorched to Romania's first male swimming world title in the 200m free.
In the 10th heat of the 100m on Tuesday morning, he was only fourth fastest at the end of the first 50m in his heat but he cruised through the field on the back half to win his race.
His time of 47.60sec was 0.35sec faster than anyone else in the 11 heats.
American Caeleb Dressel, who has dominated this event at the Olympics and worlds over the last five years, won the last heat, but was second-best on the clock to Popovici.
South Korean 19-year-old Hwang Sunwoo, the silver medallist behind Popovici on Monday, seemed to have more of a hangover, and tied for 17th.Only the first 16 advance to the semis.
The top two in the previous evening's 100m women's backstroke were also back in the pool as the session opened with a quick thrash through 50m backstroke qualifying.
Kylie Masse of Canada, who took silver the day before, was fastest followed by American Katharine Berkoff and another Canadian, Ingrid Wilm.
Monday's gold medallist, American Regan Smith, was fourth.
Australian Kaylee McKeown, the Olympic 100m back champion, who skipped that race in Budapest as she experiments with adding new events to her competition schedule, was fifth.
None of the three medallists from the last worlds three years ago are racing in Budapest.
Americans Carson Foster and Chase Kalisz topped qualifying in the men's 200 medley.
Forster won the silver in the 400m medley on Saturday when Kalisz took bronze.
The gold medallist in that event, Frenchman Leon Marchand, qualified comfortably with the eighth fastest time.
Tokyo Olympic gold medallist Wang Shun sneaked into the last 16 with the 15th best time.
Canadian 15-year-old Summer McIntosh, the silver medallist in the 400m free on Saturday, topped qualifying in the women's 200m butterfly.
American Hali Flick inger was second followed by Kina Hayashi of Japan.
China's Zhang Yunfei was sixth fastest, more than five seconds outside the personal best she set winning Olympic gold in Tokyo.
In the poker game of mixed medley relay qualifying, Italy rested all three of their gold medallists and squeaked through with the seventh best time.
Since two of their winners in Budapest, Benedetta Plato and Nicolo Martinenghi, swim breaststroke, they will struggle to play all their aces in the final.
The American team led by Ryan Murphy and Lilly King topped the qualifiers, the Dutch were second and world record holders and inaugural Olympic champions Great Britain third.
