Samuel Austin Querrey (/ˈkwɛri/; born October 7, 1987) is an American professional tennis player who (as of August 6, 2018) is ranked world No. 32 in men's singles by the Association of Tennis Professionals (ATP). Known for his powerful serve, Querrey holds the record for consecutive service aces in a match with 10. He is also a capable doubles player, with five doubles titles and a career-high doubles ranking of world no. 23.
In singles, Querrey has won ten titles. His best performance in a Grand Slam singles event was at the 2017 Wimbledon Championships, where he reached the semifinal by defeating World No. 1 Andy Murray. At the same tournament the previous year, he defeated World No. 1 Novak Djokovic to reach the quarterfinals. Other career highlights for Querrey include defeating former world number one Rafael Nadal in the Acapulco final of 2017, reaching the quarterfinals at the 2017 US Open, and, in the 2015 US Open, reaching the mixed doubles final with Bethanie Mattek-Sands and the men's doubles semifinals with Steve Johnson. He has twice reached the semifinals of the Davis Cup with the United States team, in 2008 and 2012.