KAZAN, Russia (AP) The ''Iron Lady'' from Hungary is poised for another medley sweep at the swimming world championships.
Katinka Hosszu led the 400 individual medley heats by a huge margin on Sunday, completing the grueling event in 4 minutes, 32.78 seconds, nearly three seconds ahead of second-placed Barbora Zavadova of the Czech Republic.
''I feel pretty good,'' Hosszu said. ''Of course it's going to be really tough this afternoon. There are some swimmers that have been basically preparing for this day and haven't really been racing.''
Olympic champion and world-record holder Ye Shiwen of China continued to struggle, failing to advance in 15th - more than 10 seconds slower than Hosszu.
The final was scheduled for later, one of nine sets of medals to be handed out on the final night of the eight-day meet.
Hosszu already won the 200 IM, setting a world record in the process. And she swept the medleys at the last worlds in Barcelona two years ago.
She's aiming for Ye's record of 4:28.43.
''That's really the ultimate goal,'' Hosszu said. ''We'll see how close I can get tonight.''
Hosszu arrived at this meet entered in seven individual events. Beside gold in the 200 IM, she also won a bronze in the 200 back.
Hosszu said she had no plans to enter fewer events in the future, adding that her program was ''definitely'' the right one.
Emily Overholt of Canada qualified third, while British contender Hannah Miley tied for fourth with Maya Di Rado of the United States.
Elizabeth Beisel of the U.S., the 2011 champion and Olympic silver medalist, failed to advance in 12th.
In the men's 400 IM, Chase Kalisz topped the heats in 4:11.83. David Verraszto of Hungary was second, defending champion Daiya Seto of Japan was third and Tyler Clary of the U.S. was fourth.
''I would like to go a best time overall,'' said Kalisz, who took silver in 2013. ''I would definitely like to compete for a title. That's always in the back of everyone's head, so I'm just going to go out there and race as hard as I can.''
Olympic champion Ryan Lochte wasn't entered in the 400 IM but he anchored a U.S. team also featuring Matt Grevers, Cody Miller and Tim Phillips to the top qualifying spot in the 4x100 medley relay.
It's been a tough meet for the U.S. men in the relays, having failed to reach the final in the 4x100 free and having surrendered a large lead in the anchor leg to settle for silver behind Britain in the 4x200.
''We all had great splits there and got done what we needed to get done,'' Grevers said. ''After the 400 freestyle relay, we didn't want to leave anything up to chance, so we were in the game this time.''
Australia advanced second, 0.80 behind, and France was third. Hungary was disqualified for a false start by Daniel Gyurta in the second leg.
''For the U.S., hopefully it doesn't matter who else is around, because when our four guys are on, no one's going to beat us anyway,'' Grevers said.
China led the women's 4x100 medley relay heats by a small margin ahead of the U.S and Sweden.
Associated Press writer James Ellingworth contributed.
Andrew Dampf can be followed at www.twitter.com/asdampf