Swim star Phelps beaten in first final of comeback
Michael Phelps competes in the 100m butterfly final at the Arena Grand Prix in Mesa, Arizona on April 24, 2014 - by Christian Petersen
Lochte led at the 50m mark and held on to win in 51.93sec -- second-fastest in the world this year -- while fellow American Phelps was second in 52.13, matching the fourth-fastest time of 2014.
Phelps had made it look easy in posting the fastest time of the heats at the Mesa Grand Prix in Arizona, although he said his first race in nearly two years felt "strange."
The 28-year-old, whose career has spanned four Olympics and included an astonishing 18 Olympic gold medals, looked dialed-in as he took to the blocks for the final, without the smile for the sell-out crowd of 1,200 at Skyline Aquatic Center that he had in the morning.
"I was more calm tonight," Phelps said. "I don't know if that was a good thing or not."
He had time for a good-natured exchange with Lochte after the race, however.
When Lochte told a post-race interviewer he almost started smiling at the turn, Phelps interjected: "Why? Because you were ahead?"