LONDON — Ryan Lochte’s only Olympic swim on Monday night was sandwiched between Missy Franklin’s two races. He arrived in the mixed zone after placing fourth in the 200-meter freestyle in time to see Franklin’s finish in the 100-meter backstroke on a flat-screen television set up so it faced him.

“She got it,” he said.

In his economy of words, Lochte captured perfectly not only the race but the racer. Laughing in the face of convention, the clock and the highest quality women’s 100 backstroke field in history, Franklin, 17, won her first Olympic gold medal less than 15 minutes after finishing the 200-meter freestyle semifinal. She had so little time to spare, she was given special permission to warm down in the diving well next to the racing pool while the men’s 200 freestyle was taking place.

Franklin’s backstroke time of 58.33 seconds was a half-a-second faster than her month-old American record. Emily Seebohm of Australia, who was first after the preliminaries, first after the semifinals and first after the opening 50 meters of the final, won the silver in 58.68. Aya Terakawa of Japan was third in 58.83.