RIO DE JANEIRO — The United States had never failed to take the gold medal in the men’s 4x100-meter medley relay at a nonboycotted Summer Games, and it was not about to end the streak on Saturday, not in the competitive swan song of the greatest Olympian, Michael Phelps.
The backstroker Ryan Murphy — whose split time of 51.85 seconds set a world record — and the breaststroker Cody Miller set the stage for Phelps, who swam the butterfly leg and handed the freestyle anchor, Nathan Adrian, a lead he did not surrender. The Americans won with an Olympic record time of 3 minutes 27.