In 2012, at the age of 34, Sánchez entered the 2012 Summer Olympics. He posted the fastest qualifying time, and won the final with a time of 47.63 seconds, the same as his winning time in Athens in 2004 and his fastest run for eight years. Sánchez became the oldest man to win the Olympic 400m hurdles title. He was the only Olympic medalist for the Dominican Republic until 45 minutes after his second gold medal, when Luguelín Santos picked up a silver medal in the 400 metres. For his performance in London Sanchez was awarded the Laureus World Comeback of the Year.