Phelps, the 14-time Olympic champion, suffered three defeats over the two days of competition in the short-course event during which his US team set eight world records.

Rock relegated Phelps to second in the 200 metres butterfly, but the 22-year-old Briton was wearing a performance-enhancing suit while the Olympic and world champion donned his Speedo textile swimsuit.

The Briton described it as "a fantastic experience, a pleasure to race the Americans" at the Manchester Aquatics Centre.

Phelps was also beaten into third in the 200m freestyle in a meet which marks the final time the polyurethane suits will be worn in serious international competition before the return to textiles on January 1.

Phelps said: "What I'm looking forward to is being the best I can for 2012.

"I want to see who can keep themselves in shape and who can work the hardest.

"It will be more of a sport and not just putting on a suit."

The meeting ended with an emphatic 185-78 victory for the US who set eight world records in total, three today from Rebecca Soni in the 200m breaststroke, Julia Smit in the 200m individual medley and the men's 4x100m freestyle, including Phelps.

It means the number of records broken since the introduction of the high-tech suits in February 2008 breaks the 250 mark.

The European side, comprising athletes from Britain, Germany and Italy, claimed nine victories, eight by British swimmers of which six were women who continued their sustained excellence.

Britain's double Olympic champion Rebecca Adlington triumphed in the 800m freestyle and the 20-year-old expressed her delight at the win.

She said: "I'm really pleased with that swim.

"It's so much fun. To have the USA team to come over here is such a big thing.

"We are just getting better and better."