Images courtesy of NBCOlympics.com on Copacabana Beach in Rio de Janeiro.
As Jarrod Poort of Australia completed the first lap in 28 minutes 41 seconds in a commanding lead, many of rest of the pre-race medal favorites are taking the race pace of Poort into stride.
American Jordan Wilimovsky sits in 21st place swimming comfortably, as is Allan do Carmo of Brazil (13th) and Richard Weinberger of Canada (14th) under the relatively calm conditions on Copacabana Beach.
But the trailing pack is constantly changing formation, shape and direction, occasionally splitting up into two chase groups and then coming together.
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