Yannick Agnel, the Olympic champion, led at 50.64 after 100 with Ryan Lochte in third. Agnel was up by nearly 1.5 seconds at 150 with Danila Izotov and Lochte in line for second and third.
But Conor Dwyer came from behind to surprisingly keep Lochte, the defending world champ, from medaling.
Agnel is coached by Michael Phelps‘ former coach, Bob Bowman.
Dwyer, 24, wins the first individual major international medal of his career.
Lochte, who wore lime green sneakers in his walk out to the deck, is scheduled for five more events in Barcelona. He swims in the 200 individual medley prelims Wednesday morning and semifinals Wednesday evening.
“I just tried to hit my last turn,” Dwyer told Universal Sports. “Michael (Phelps?) was texting me yesterday, ‘Stop taking it out like a little girl.”
Gold: Yannick Agnel (FRA) 1:44.20
Silver: Conor Dwyer (USA) 1:45.32
Bronze: Danila Izotov (RUS) 1:45.59
4. Ryan Lochte (USA) 1:45.64
5. Kosuke Hagino (JPN) 1:45.94
6. Robbie Renwick (GBR) 1:46.52
7. Cameron McEvoy (AUS) 1:46.63
8. Thomas Fraser-Holmes (AUS) 1:47.11
British Paralympic champion Josef Craig was disqualified from a race because he didn’t cover up an Olympic rings tattoo on his chest at the IPC European Championships on Sunday.
Craig, 19, was disqualified because of an International Paralympic Committee swimming rule that states, “body advertisements are not allowed in any way whatsoever (this includes tattoos and symbols).”
Craig, who did not have the tattoo when he took gold at London 2012, has since competed at the European Championships with the Olympic rings tattoo covered.
If people attend the Paralympics, which are held weeks after the Olympics at the same venues, they will very often see the Paralympic Agitos logo where the Olympic logo once appeared.
It is visual proof that the International Olympic Committee and the International Paralympic Committee are separate entities.
At the London Paralympics, American Rudy Garcia-Tolson earned silver in a 200m individual medley with an Olympic rings tattoo visible near his left shoulder-blade.
An IPC spokesperson said the rule pertaining to the Paralympics — which covers all sports — was new going into 2012 and will be fully enforced for the first time in Rio.
MORE: London gymnastics medalist gets elaborate Olympic tattoo
Missy Franklin broke into tears reading a letter to her parents in a mock press conference in a spot for Minute Maid, one of the four-time Olympic champion’s sponsors since turning professional a year ago.
It was filmed in April near her home in Denver.
Franklin has split time training and competing and working with companies including GoPro, Laureus, Minute Maid, Speedo, United Airlines, Visa and Wheaties.
Franklin has said the sponsor commitments will curtail in the middle of May, when she starts a blackout period to focus on training for the U.S. Olympic Trials, which are June 26-July 3 in Omaha and air on NBC Sports.
VIDEO: Franklin revisits ‘biggest sacrifice’ in GoPro series finale