ROME — Michael Phelps had every reason to be satisfied after the Beijing Olympics. Yet he kept insisting there was more to do in the pool.

Clearly.

Even coming off his longest layoff and the embarrassment of being photographed inhaling from a marijuana pipe, Phelps turned in another remarkable performance over eight days at the Foro Italico. He completed it last night by helping the U.S. 400-meter medley relay team set the 43rd world record of the fastest meet in history.

OK, he didn't win another eight golds. This time, he made do with five golds and a silver.

Still, Phelps showed plenty of fire, even when there's really nothing left to prove.

"I never want to look back on my career and ask, 'What if?' " he said.

Swimming the butterfly leg, Phelps helped the U.S. pull away from Germany and Australia to win in 3 minutes, 27.28 seconds. That easily broke the mark of 3:29.34 set by the Americans at last summer's Olympics, another relay team that included Phelps.

"That relay brings out the best in me," Phelps said. "It doesn't matter how much energy I have, it's all going to go into every race. That's one of the things that I enjoy most — stepping out onto the blocks no matter what kind of shape I'm in."

Meanwhile, Eric Shanteau, who overcame testicular cancer to swim his best times, picked up the first major gold medal of his career on the breaststroke leg of the relay, to go along with a silver and a bronze in Rome. The other members of the winning team were backstroker Aaron Peirsol and freestyle anchor David Walters.

Shanteau was thrilled to finally step on the top rung of the podium. Last summer, he learned just before the U.S. Olympic trials he had cancer. He put off treatment until after the games, underwent surgery when he got home and has been cancer-free since.

"What a great way to end it," said Shanteau, who had missed an individual gold by one-hundredth of a second in the 200 breaststroke. "To finally get it, that gold medal, was an unbelievable feeling."

Also yesterday, Ryan Lochte won his fourth gold of the championships and Germany's Britta Steffen matched her 50-100 freestyle sweep in Beijing.

No such glory for 42-year-old Dara Torres. The senior citizen of the pool finished last in her only individual final at the Foro Italico.

"I like to win, but eighth fastest in the world at 42, so I can't be too disappointed," she said.

Torres failed to match her silver-medal showing from the Olympics, when she finished just one-hundredth of a second behind Steffen. Bothered by a sore knee that will require surgery, the American was eighth in 24.48.