He made his debut in singles on the ATP World Tour in July 2014 at the Citi Open , where he qualified for the main draw, but lost there in three sets in the opening round against Rajeev Ram . He also competed in doubles and formed a doubles pair with Stefan Kozlov. You clearly lost the game in two sets. For the second time on the World Tour, Donaldson played at the US Open 2014, but also lost here in the first main round against Gaël Monfils clearly in three sets. In doubles, where he won the first round alongside Michael Russell , he was eliminated in two sets in the second against Bob and Mike Bryan .
At the US Open 2016 he was able to achieve his first victories at Grand Slam level over David Goffin and Viktor Troicki , who were better positioned in the world rankings . He lost to Ivo Karlović in three sets in the third round . In 2017 Donaldson was able to reach the third round of a Grand Slam tournament at Wimbledon for the second time in his career. There he was defeated by Dominic Thiem in three sets. After the tournament, Donaldson reached a new career record with world number 58.
_(29569818640).jpg)
United States
