Michael Phelps took another small step toward next year's Olympics, and this time it was a winning one.

After losses in his first two events at the world championships, Phelps won the 200-metre butterfly for a record fifth time Wednesday. His time of one minute 53.34 seconds was well off the world mark he set two years ago in Rome, but these days, Phelps incrementally measures his progress.

"It was 1½ seconds faster than last year," he said. "I felt like myself the last 100 of that race, especially that last 25. I didn't feel like I was dying and barely able to get my arms out of the water and like there was a piano on my back."

The two-time Olympic 200 fly champion went out fast, leading Japan's Takeshi Matsuda through the first 100 metres before Matsuda overtook him on the final turn. Phelps fought back, and surged ahead for good a few metres into the last lap.

Matsuda earned the silver at 1:54.01, while China's Wu Peng, who had dealt Phelps two losses in his "bread-and-butter" event this year, took bronze at 1:54.67.

"What he doesn't have is that kick on the last 50 where he just leaves everybody, so that's the next step," Phelps' coach Bob Bowman said.

Italy's Federica Pellegrini made history on the fourth night of the eight-day meet at the Oriental Sports Center. Pellegrini won the 200 freestyle to become the first woman to sweep the 200 and 400 at consecutive worlds, joining Australian great Ian Thorpe.

In the stands, Phelps' mother Debbie looked relieved, while his sister Hilary and girlfriend Nicole Johnson immediately began texting on their cellphones.

"I'm super happy with swimming faster than I did last year, but I still want more in that event," he said. "I want to be faster. That was a little too close for my comfort, but that's the race I sort of came on the scene with in 2000."

The 10th anniversary of his first 200 fly world title set Phelps to reminiscing, something he's willing to do now that he's nearing the end of his historic career.

He set a world record in his 2001 win. Back in Baltimore, he looks at a picture of himself from that meet every day while training at his home club.

"I think I look so young, but was I was 15, 16 at the time," he said.

Phelps defended his title at the 2003 worlds in Barcelona, skipped the event in 2005 ["We were being dumb," Bowman said], then reclaimed it in 2007 at Melbourne.

"I remember breaking the world record by a little over a body length," he said.

Two years ago in Rome, he lowered his world mark again.

"I remember taking it out as fast as I could and hoping to hang on the last 50, and I think that made it one of the most painful I've ever had in the 200 fly," he said.

Phelps led off the 4x100 relay when the United States took bronze on the opening night of the meet Sunday, then settled for silver behind teammate Ryan Lochte in the 200 free Tuesday.

"I had written down in my journal all the times I wanted to do at this meet, and so far I'm on pace," Phelps said. "Every single one that I've written down, I'm right at it."

Finally winning a race was a shot of confidence for Phelps, who has 14 Olympic gold medals and a record 23 world titles.

"We need a little pat on the back," Bowman said. "Everybody needs that."

Pellegrini rallied from seventh early in the race to fifth at the halfway mark and was third heading into the final lap before hitting the wall in 1:55.58.

"You've just got to always believe in yourself. It's great to be a part of history," she said. "This was my race, and nobody was going to enter my house."

Kylie Palmer of Australia won the silver in 1:56.04, and Camille Muffat of France took the bronze in 1:56.10.

China's Sun Yang won the 800 freestyle, giving the host country its third gold medal and eighth overall in the pool. Sun led all the way in the non-Olympic event and touched first in seven minutes 38.57 seconds.

"The victory gives me more confidence ahead of the remaining races and next year's London Olympics," said Sun, who finished second in the 400 free.

Sun broke away from the medallists ' parade and climbed into the stands, smiling and high-fiving fans before giving away the stuffed animal the medallists receive. Ryan Cochrane of Victoria was second and Gergo Kis of Hungary took third.

"When he won the gold medal two years ago in Rome, I was blown away by the idea that one day I would be a world champion," Sun said. "I'm glad that I made it."

Sun's teammate, Zhang Lin, didn't defend his title because Chinese team officials said he was out of shape.

In another non-Olympic event, Brazil's Felipe Silva beat Italy's Fabio Scozzoli in the 50 breaststroke, with defending champion Cameron van der Burgh of South Africa finishing third.

Phelps and teammate Lochte will resume their rivalry in the 200 individual medley on Thursday. Lochte was the fastest qualifier in the semifinals, with Phelps 0.52 seconds behind.

"He's not going to give up and neither am I," Lochte said.