American swimmers had won the men's 200-meter backstroke at each of the previous five Olympic Games entering Rio, and thanks to Ryan Murphy the streak is now at six.
Murphy, who used a fast turnover rate to win the 100m backstroke on Monday, lengthened his stroke out for the grueling 200. Reigning world champion Mitchell Larkin of Australia appeared to be gaining on Murphy but the 21-year-old American finished hard for the win in 1 minute, 53.62 seconds.
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It's the second medal of these games for Murphy, who is also expected to take home gold as a member of Team USA's 4x100m medley relay on Saturday.