RIO DE JANEIRO (AP) — It was a Dutch sweep at Copacabana.
Their first Olympic gold in open water swimming was never in doubt.
The second one took a few minutes to sort out.
Ferry Weertman of the Netherlands beat Greece's Spiros Gianniotis in a photo finish Tuesday off one of the world's most iconic beaches, a frenetic finish to a 10-kilometer marathon that was in striking contrast to Sharon van Rouwendaal's dominating victory the previous day.
While the women's race was decided by a whopping 17.4 seconds, a pack of men's swimmers led by Gianniotis powered into the finish chute stroke for stroke as hundreds of cheering, swimsuit-clad fans ran along the beach to watch the ending.
The medals were in doubt until the very end — and even for a bit longer after that, as the officials tried to sort things out.
Gianniotis appeared to go under the finish line first, but he had to reach back to grab the timing pad. Weertman got his hand on the pad a split-second ahead of the Greek swimmer — a finish so close they were both credited with the same time, 1 hour, 52 minutes, 59.8 seconds.
"Even after I touched the wall, I wasn't sure I'd won," Weertman said. "It took me a while. I called my friends back home and they said, 'You won, you won!' and I'm like, 'Oh really?' I couldn't believe it. I still can't believe it."
The 36-year-old Gianniotis missed a chance to give Greece its first swimming gold since the inaugural Summer Olympics in 1896. He has competed in all three open water events since the sport was added to the Olympic program in 2008, but this was his first medal.
It was also the final event of his career.
"Every single meter of the training, every single day and hour, it's just come down to the perfect moment," Gianniotis said. "I think that's a really good way to go."
The bronze went to France's Marc-Antoine Olivier, who out-touched China's Lijun Zu in another result that required a photo to sort out. Britain's Jack Burnell appeared to touch third, but he was disqualified for a tussle with defending Olympic champion Ous Mellouli just a few meters from the line.
It was the second day in a row that a medal was stripped away because of rough tactics in the chute. On Monday, France's Aurelie Muller lost the silver when she collided with Italy's Rachele Bruni right at the finish. This time, the ruling went France's way.
"It's only when I got into the boat that I knew my position," Olivier said. "Then I started crying."
American Jordan Wilimovsky was fifth. He briefly grabbed the lead on the final lap, but got stuck in the middle of a pack of swimmers and finished 3.4 seconds behind.
"It's just the nature of the event," Wilimovsky said. "It comes down to touch finishes sometimes. Congrats to the guys that did really well. It was a really tough race."
Trying to duplicate Van Rouwendaal's strategy, Australia's Jarrod Poort broke away from the pack in the early going, building a huge lead of more than a minute at the midway point.
He couldn't hold on, getting passed on the last of four laps around the bay and finishing 20th.
Mellouli, in what was likely his final Olympic race, settled for 12th.
Once again, there were no complaints about the water quality at Copacabana, which was the subject of much scrutiny in the lead-up to the games after an Associated Press report that found potential health risks caused by the dumping of raw sewage into the waters around Rio.
"It was great," Wilimovksy said. "I didn't notice anything wrong or anything bad. It was really nice. The water temperature was really good. It was just fun to be out there."
Another American swimmer, Sean Ryan, took antibiotics and probiotics to ward off any potential health risks.
"I did as much as I could to prevent illness," Ryan said. "We'll see what happens in the next two weeks. We may be playing roulette with it, but we prepared as well as we could."
Ryan said it seemed like any other normal ocean race, which calm conditions off the hotel-line beach making things easier for the competitors.
"Your mouth feels all funky afterward," he said with a smile, "like a normal salt water race."
Follow Paul Newberry on Twitter at www.twitter.com/pnewberry1963 . His work can be found at http://bigstory.ap.org/content/paul-newberry .