Diego Sebastián Schwartzman (born 16 August 1992) is an Argentine professional tennis player competing mainly on the ATP Tour, both in singles and doubles. He reached the semifinals of Istanbul in 2015 and won his first title there in 2016.
Schwartzman reached a career-high ATP rankings of world No. 33 in singles on August 2017 and No. 69 in doubles in April 2015.
In 2010 he won the Bolivia F3 Futures (CL), in 2011 he won the Chile F14 Futures (CL). In 2012, he won titles at the Peru F2 Futures (CL), Argentina F11 Futures (CL), Argentina F14 Futures (CL), Argentina F20 Futures (CL), Argentina F21 Futures (CL), Argentina F22 Futures (CL), and Buenos Aires Challenger (CL). At the 2013 Australian Open, he lost in the final round of qualifying.
Diego made his first appearance in the main draw of a Grand Slam event at the French Open, he came through qualifying before making it to the second round, where he lost to Roger Federer. He lost in the first round of the US Open to Novak Djokovic.
Schwartzman's best result of the season came at the 2015 Istanbul Open where he reached the semifinals, beating former top ten player Jurgen Melzer along the way. In the semis he faced tennis legend Roger Federer. Schwartzman won the first set decisively before ultimately falling 7-5 in the final set. He was also part of the Argentine Davis Cup team, which reached the semifinals in 2015.
Diego won his first ever singles title at the 2016 Istanbul Open - an outdoor 250 clay court event. He impressively defeated established top player Grigor Dimitrov in the final, coming back to win 6-0 in the final set after losing the first set in a tie-break. Later, Dimitrov excused his behavior during the match, after he smashed three rackets, which ultimately led to a warning, a point penalty and then another point penalty. The second and final point penalty came with Dimitrov down 5-0 and gave the game, set and match to Schwartzman. In October he reached his second final at 250 level, in Antwerp. He lost to Richard Gasquet 6-7, 1-6 in the final.