Matthew Grevers (born March 26, 1985) is an American competition swimmer who competes in the backstroke and freestyle events, and is a six-time Olympic medalist. He has won a total of twenty-four medals in major international competition, twelve gold, nine silver, and three bronze spanning the Olympics, World Championships, and the Universiade. At the 2008 Summer Olympics, Grevers won gold medals as a member of the U.S. teams in the 4×100-meter freestyle and 4×100-meter medley relays, and a silver medal in the 100-meter backstroke. Four years later at the 2012 Summer Olympics, he won a gold in the 100-meter backstroke.
At the 2012 United States Olympic Trials, the qualifying meet for the 2012 Olympics, Grevers qualified for the U.S. Olympic team by finishing first in the 100-meter backstroke and third in the 100-meter freestyle. In the final of the 100-meter backstroke, Grevers won in a time of 52.08 seconds, the second-best effort of all time and just behind Aaron Peirsol's world record of 51.94. Grevers recorded the fastest time in a textile suit in the 100-meter backstroke. In the 100-meter freestyle, Grevers placed third with a time of 48.55, which ensured him a spot on the 4×100-meter freestyle relay. Grevers also competed in the 50-meter freestyle, and placed sixth in the final with a time of 22.09.
At the 2012 Summer Olympics in London, Grevers won a total of three medals: two golds and one silver. Grevers earned his first medal, a silver, by swimming for the second-place U.S. team in the preliminary heats of the 4×100-meter freestyle relay. In the final, the American team finished second behind France. Teaming with Jimmy Feigen, Ricky Berens, and Jason Lezak in the heats, Grevers swam the second leg and recorded a time of 47.59. After leading the heats (52.92) and semifinals (52.66) of the 100-meter backstroke, Grevers won gold in the final of the 100-meter backstroke with a time of 52.16, bettering Aaron Peirsol's Olympic record of 52.54 set in 2008 and 0.76 s ahead of Nick Thoman. For Grevers, it was his first individual gold medal. In his final event, the 4×100-meter medley relay, Grevers won gold with Brendan Hansen, Michael Phelps and Nathan Adrian. Swimming the backstroke leg, Grevers recorded a time of 52.58 seconds, and the U.S. team went on to win with a time of 3:29.35.
At the 2013 FINA World Championships in Barcelona, Grevers achieved a total of two medals: a gold and a silver. On the first night of swimming, Grevers missed the top-eight championship roster in the 50 m butterfly, as he finished his semifinal run with a twelfth-place time in 23.35. The following day, Grevers threw down the event's fastest time of 52.93 to claim the gold medal in the 100 m backstroke, finishing ahead of his teammate David Plummer by nearly two-tenths of a second. On the final night of the meet, Grevers swam his last two finals with only 45 minutes in between. First, he posted a matching time of 24.54 to share the silver medal with France's Jérémy Stravius in the 50 m backstroke. Nearly an hour later, Grevers teamed up with Kevin Cordes, Ryan Lochte, and Nathan Adrian for the final in the 4×100 m medley relay. During the race, Grevers swam the backstroke leg and touched the wall with a split of 53.02 until his teammate Cordes left the block 0.04 seconds early on the breaststroke leg, smashing the medal chances entirely for the Americans with a disastrous disqualification.