CHARLOTTE, N.C. (AP) Olympic champions Michael Phelps and Ryan Lochte remained winless heading into the final day of the Arena Pro Swim Series-Charlotte meet.
Lochte finished fourth Saturday in the 100-meter backstroke, won by Serbia's Arkady Vyatchanin.
Meanwhile, Phelps - in his second meet since serving a six-month suspension - was seventh in the 200 butterfly, won by Chase Kalisz.
Lochte finished the event in 54.43 seconds - nearly three-quarters of a second behind Vyatchanin, who won in 53.69. Lochte barely missed out on medaling, coming in 0.01 seconds behind Japan's Junya Koga.
''That was my best in-season time,'' Lochte said. ''It was a good day. I'm thinking about getting better day after day.''
Phelps had a harder time in the 200 butterfly, which he had not competed in since earning the silver medal in the 2012 London Olympics. He touched in 2:00.77, more than 3 seconds behind Kalisz, who won in 1:57.58.
The duo had a potential matchup in the 100 backstroke. But Phelps withdrew from the event Saturday morning to focus on the 200 butterfly.
Phelps and Lochte have two more potential head-to-head matchups Sunday at the Mecklenburg County Aquatic Center - the 200 individual medley and 100 freestyle.
Other men's winners Saturday were Josh Schneider (50 freestyle), Josh Prenot (200 breaststroke), Brazil's Cesar Cielo (50 butterfly), and Connor Jaeger (400 freestyle).
Schneider, the former world record holder in the 50 freestyle, won the event Saturday in 21.96, just 0.09 seconds ahead of Cielo.
Prenot won the 200 breaststroke in 2:09.30, finishing more than 2.3 seconds ahead of Cody Miller. Miller touched in 2:11.63.
Cielo, the gold medalist in the 50 freestyle at the 2008 Beijing Olympics, won the 50 butterfly in 23.26, beating Tim Phillips by nearly a half-second. Phillips touched in 23.71.
Jaeger won the 400 freestyle in 3:46.30, more than 1.2 seconds ahead of Conor Dwyer. Dwyer touched in 3:47.53.
Hungary's Katinka Hosszu added two more women's event wins to her total Saturday, the 200 butterfly and 100 backstroke. Arianna Vanderpool-Wallace was also a two-time winner, in the 50 freestyle and 50 butterfly. Other winners were Micah Lawrence (200 breaststroke) and Leah Smith (400 freestyle).'
Hosszu, who won the 200 freestyle and 400 individual medley on Friday, won the 200 butterfly in 2:08.00, 0.76 seconds ahead of Cammile Adams. She added the 100 backstroke title about 15 minutes later, winning in 59.47, 0.39 seconds ahead of Kathleen Baker.
Vanderpool-Wallace won the 50 freestyle in 24.35, beating 12-time Olympic medalist Natalie Coughlin by 0.68 seconds. She then won the 50 butterfly in 25.93, 0.38 seconds ahead of Claire Donahue.
Lawrence dominated in winning the 200 breaststroke, with her time of 2:24.61 just over two seconds ahead of runner-up Martha McCabe. McCabe finished in 2:26.69.
Smith won the 400 freestyle in 4:07.45, beating Denmark's Lotte Friis by 0.84 seconds. Friis, the former world champion in the 1,500 freestyle, touched in 4:08.29.