On day seven, Dressel became the first swimmer ever to win three gold medals on a single day. He won the 50 meter freestyle in 21.15, a new world textile best time. Half an hour later he won the 100 meter butterfly in 49.86, again a new world textile best and 0.04 seconds above the world record held by Michael Phelps. The third gold medal came in the 4×100 meter mixed freestyle relay, where he led off in 47.22. Dressel and teammates Adrian, Comerford, and Manuel broke the world record for this relay with a time of 3:19.60.