Michael Phelps loses in first final

— -- MESA, Ariz. -- Michael Phelps has lost in the first final of his comeback after a 20-month retirement.

Ryan Lochte beat Phelps in the 100-meter butterfly final at the Arena Grand Prix. Lochte touched in 51.93 seconds; Phelps was second in 52.13 on Thursday night.

Phelps is the three-time Olympic champion and current world record-holder in the event. He was competing for the first time since the 2012 London Olympics.

"I felt like a summer league swimmer today," Phelps said, smiling, after the heat. "I felt like I should have my heat and lane written on my hand so I didn't forget it."

Lochte was second-quickest, winning his heat in 52.94.

Phelps and Lochte joked with each other behind the starting blocks when Phelps came out early for his heat, which came after Lochte's.

"He said, 'Maybe we should both just mess around and see if we can both get in the 'C' final,'" Phelps said.

Longtime coach Bob Bowman liked what he saw from Phelps' qualifying heats.

"I could tell when he came in that it was going to be good, that he was into it," he said.

"It really is wild. It's good for the sport," Phelps said about his reception. "This is the sport I've known my whole entire life and loved my whole life. When I heard the roar in the stands, it's amazing."

Retired speedskater Apolo Anton Ohno, the most decorated U.S. Winter Olympian, tweeted good luck to Phelps, saying, "Excited to see you back brother."

The three-day meet sold out every session the day Phelps' comeback was announced last week, with a capacity of 1,200 at Skyline Aquatic Center. A pair of $40 all-session tickets was being advertised online for $250. USA Swimming issued 100 media credentials -- five times more than usual.

Information from The Associated Press was used in this report.