Finke breaks world record to win men's 1500m freestyle gold
After 30 lung-busting laps, Finke touched the wall in 14 minutes, 30.67 seconds at La Defense Arena, eclipsing Sun Yang's 12-year-old mark of 14:31.02 set at the London Games.
Gallant Italian Gregorio Paltrinieri took silver, 3.88 seconds behind Finke, with Daniel Wiffen, the 800m gold medallist, taking the bronze for Ireland.
Finke became the first male swimmer to go back-to-back in the gruelling event since Australia's Grant Hackett in 2000-04 and the first American since Mike Burton in 1968-72.
It gave the USA their seventh gold medal of the meet, the team leapfrogging Australia to the top of the table on the last night of competition.
Australia, who also have seven golds but fewer medals in total, will need to win at least one of the two remaining medley relay events and hope the USA miss out on more gold to take back the top spot.
Three years after winning the 800m and 1,500m golds at Tokyo, Finke marked his place among the titans of distance swimming with an aggressive swim which he led from start to finish.
He was a full body length ahead of Paltrinieri and Wiffen by the 300-metre mark.
Paltrinieri made a charge near the 600-metre mark and pulled up to Finke's waist, but there was no stopping the American.
Ireland's first men's Olympic swimming champion, Wiffen had tipped a world record would be needed to take gold and hoped he would be the man.
It was Finke, though, producing something special to hold on for the world record and send the La Defense Arena crowd into hysteria.