Phelps grabbed his first major victory since returning to the pool, swimming for the U.S. men in the 800-meter freestyle relay at the Pan Pacific Championships in Australia.
"We all swam great legs of that relay, and we got the job done that we needed to," he said, adding that the victory "should propel us into worlds next summer, and hopefully on to Rio from there."
Things did not go as well for the 29-year-old Phelps in the 100 freestyle, where he finished fourth. Cameron McEvoy of Australia won that event in 47.82 seconds.
Competing outdoors in cool, rainy conditions along the Gold Coast, the Americans collected four gold medals, three silver and three bronze on Friday.
"I overcame the bad weather," Hardy said. "Normally I like the warm sunshine. I'm a bit of a diva, but I did a good job tonight."