Dimitrov broke into the world's top 10 back in 2014 but the 26-year-old slipped to world No 40 just two years later.
However, he ended a three-year title drought when winning in Brisbane in January, and he followed up that victory Down Under with a run to the semi-finals of the Australian Open.
Dimitrov fell to losing finalist Rafael Nadal in the last four, but he did go on to win a second ATP title of the year when downing David Goffin in Sofia, Bulgaria.
The clay season was one to forget for Dimitrov - as he suffered early exits in Monte Carlo and Rome - while he was dumped out of the French Open by Pablo Carreno Busta in the round of 32.
Dimitrov is much stronger on grass, and he will look to better his semi-final finish of 2014 when heading to Wimbledon this July.