Rubin trained as a youth at the John McEnroe Tennis Academy on Randalls Island in Manhattan, New York . Up to the age of seven he competed in various U12 events and at the age of eleven he won his first international tournament in his age group. In 2010 he reached the final at Le Petits As , one of the most important junior tournaments in the world, which he lost in straight sets to Quentin Halys . In 2012, he won the Copa del Café in Costa Rica , a junior tournament organized by the International Tennis Federation . In 2014 Rubin reached position six in the junior world rankings and was also the number 1 junior in the USA. At the Junior Grand Slam tournament in Wimbledon in July 2014, he won his first Grand Slam title. In the final he defeated his compatriot Stefan Kozlov in three sets with 6: 4, 4: 6 and 6: 3.
Career
Rubin made his debut on the ATP World Tour in 2014 in Winston-Salem , where he received a wildcard and met Bradley Klahn in the first round . Although he won the second set 6-0, he ultimately left the field as a loser. He played his first game in a Grand Slam tournament with the pros at the 2014 US Open , where he received a wildcard in singles and doubles , together with Stefan Kozlov. In both competitions he was eliminated in the first round.