Michael Phelps of the US looks at his bronze medal for the men's 4X 100m freestyle final at the 14th FINA World Championships in Shanghai, July 24, 2011. [Photo/Agencies]

Michael Phelps got off to a losing start at the world championships, and it wasn't his fault. He put his teammates in second place on the opening leg of the 4x100-meter freestyle relay. They just couldn't move up.

Kicking off the first of his seven events at the eight-day meet, Phelps led off a surprising bronze-medal showing in the relay Sunday at the Oriental Sports Center. It was the first time since 2007 that the American men lost a relay of any kind at worlds or the Olympics.

Phelps said "it's frustrating, it's not how we want to start it."

They were upset by the Australians, who got an opening-leg split of 47.49 seconds from James Magnussen and went on to win in 3 minutes, 11.00 seconds.

No return after London Games

Phelps reaffirmed on Saturday that London would be his last Olympics in his swimming career despite the fact that some retired swimmers had come back to the pool.

"No!" On whether one day after London he would return, Phelps gave his denying answer in the press conference one day before the start of the swimming competitions at Shanghai world championships.

The 14-time Olympic gold medallist, who set an unprecedented eight-gold feat at Beijing Olympics, said it was weird to always look back the career and live on the memory and experiences he had gone through.

He said he wanted to move on and try something new after London Games as everybody in their lifetime wants to go forward.

"I'll be fighting for the next year and start to move on and try some other things....I'll have fun." said the 26-year-old.

Phelps, who collected five golds in the last worlds, might swim in seven disciplines including 100m and 200m butterfly and some relays according to the USA Swimming official website.