The 26-year old, who has so often been criticised in the past for failing to match his potential, has put in one of the best seasons of his career, with three ATP tour titles and a Grand Slam semifinal helping him join Roger Federer, Rafael Nadal, Alexander Zverev, Dominic Thiem, and Marin Cilic (who qualifies in sixth behind him) at the season-ending showpiece.
With both Dimitrov and Cilic securing qualification for the final ATP event of the year, only two spots are left for the tournament. David Goffin and Pablo Carreno Busta currently sit in the final qualification places, though Kevin Anderson, Sam Querrey, and Juan Martin del Potro are all still in the hunt.
Dimitrov qualifies after season-best year
It has hardly been a flawless season for Dimitrov, who has struggled on some occasions, though in general the Bulgarian has played fairly well in 2017 and has been rewarded with a maiden showing in London; he narrowly missed out three years ago after a poor end to the season.
The world number eight started the season incredibly well, winning his first title in two and a half years at the Brisbane International in January, before reaching the last four at the Australian Open and then taking a second title of the season on home soil at the Sofia Open. Dimitrov then struggled slightly through the middle part of the season, though reached the last four at Queen's and the second week at Wimbledon, before capturing the first Masters 1000 title of his career in Cincinnati.
Dimitrov could have sealed qualification for the World Tour Finals in Sunday, though failed to do so as he fell to Juan Martin del Potro; however, it did not prove to be important, with early losses for both Kevin Anderson and Sam Querrey this week securing qualification for both him and Marin Cilic. He is currently set to be the fifth seed in London, though the final seedings will not have been decided until the conclusion of the Masters 1000 event in Paris next week.