dropping a set, the Bulgarian reached the fourth round at Wimbledon, but then lost in straight sets to eventual champion Roger Federer in what was his sixth defeat in six official matches with the Swiss. Dimitrov returned to the top ten for the first time since February 2015 at the conclusion of the tournament. Dimitrov returned to hard courts in August. After reaching third rounds at the Washington Open and the Rogers Cup in Montreal, the Bulgarian won his first Masters 1000 title in Cincinnati, defeating Nick Kyrgios in the final in straight sets, winning the tournament without losing a set. Dimitrov then reached the second round of the US Open, where he lost to teenager Andrey Rublev. In the beginning of October, Dimitrov reached the semi-finals in Beijing after wins over Juan Martín del Potro and Roberto Bautista Agut, and then the quarterfinals of the Shanghai Masters. In both events the Bulgarian was eliminated by world No. 1, Rafael Nadal, in three-setters. Dimitrov then advanced to the final of the Stockholm Open with wins over Jerzy Janowicz, Mischa Zverev and Fabio Fognini but lost to US Open semifinalist del Potro in straight sets. This was Dimitrov's third final in Stockholm. In the following week, Dimitrov was confirmed to participate for the first time at the ATP Finals, thus becoming the first Bulgarian to qualify for the season-ending championships. Afterwards, he decided to skip the Vienna Open (despite being given a wild card) due to fatigue, and to prepare for the Paris Masters the following week, where Dimitrov grabbed third victory in a row over Richard Gasquet before losing in the third round to big serving John Isner in three sets. On the following week, prior to the ATP Finals, Dimitrov achieved a new career high, climbing to world No. 6 position. Dimitrov was drawn in the Pete Sampras group of the 2017 ATP Finals, together with Rafael Nadal, Dominic Thiem and David Goffin. Playing with Thiem in his debut match, Dimitrov clinched a maiden victory in the ATP Finals in a tight three-setter. The Bulgarian then routed Goffin, allowing only two games to his opponent. With this win Dimitrov won the first place in the group and secured his place at the semi-finals. Dimitrov stayed perfect in the group after another convincing victory, this time against alternate Pablo Carreño Busta. The Bulgarian came back from a set down to