AP Photo/Dmitri Lovetsky

If Michael Phelps' first gold of the Rio Games will be knowns as "The Turn," his last should be dubbed, "The Peek."

When Phelps jumped into the pool for the third leg of the 4x100-meter medley relay on Saturday night, the Americans were just behind Great Britain in second place.

AP Photo/Lee Jin-man
In the first 50 meters of the butterfly stroke, Phelps was able to pull even with James Guy. The two swimmers were neck-and-neck as they hit the wall for the turn and, while underwater, Phelps took a long look to his left to see where he stood in the race. Guy was right in his line of sight, and that's when Phelps really turned on the jets.

Over the final 50 meters Phelps pulled away from Guy, putting some distance between the United States and Great Britain. Nathan Adrian surged off the block for the freestyle leg, and the Americans celebrated Phelps' 23rd career gold medal. 

It was another tremendous swim for Phelps in what he says is his last Olympics. He opened the Rio Games by leading the U.S. to victory in the 4x100 freestyle relay when he unleashed what coach Bob Bowman called the best turn he's ever seen in a pool to blow away France's Fabien Gilot. The flip turn gave the Americans an enormous cushion that allowed them to comfortably close out the race.

It started with a turn. It ended with a peek. And it came up golden.