Reilly Opelka (born August 28, 1997) is an American professional tennis player. At 6 feet 11 inches tall, he is tied (with Ivo Karlović) for the tallest-ever ATP-ranked player, and can produce serves that measure over 140 mph. He has been ranked as high as World No. 17 in singles by the ATP, which he achieved on February 28, 2022, and in doubles as world No. 89 on August 2, 2021. He has won four ATP singles titles and one doubles title. He is a junior Wimbledon champion.