LONDON • Grigor Dimitrov has set his sights on winning his first Grand Slam after his dramatic victory at the ATP Finals on Sunday gave him the biggest title of his career.

As the Bulgarian stood centre stage holding aloft the gleaming trophy and the ticker tape rained down, it felt like a weight had finally been lifted from his shoulders.

It was not the Grand Slam title he wants most, but the next best thing and it felt like a breakthrough moment for a player widely perceived as one of the game's underachievers.

He played calmly and intelligently to beat Belgium's David Goffin 7-5, 4-6, 6-3 in a superb climax to the season. But he was wary about getting caught up in the moment.

"The important thing is just to stay on the ground and put your head down, work even harder," Dimitrov told reporters.

"I just want to keep the same line. I don't want to get too hyped up because I've done well. No, this makes me even more locked in, more excited about my work, and for what's to come."

Back in 2008, the Bulgarian won the junior Wimbledon title against Henri Kontinen, who won the doubles crown at the O2 Arena on Sunday, and it was not long before he was being dubbed the natural successor to Swiss great Roger Federer.

The "Baby Fed" tag proved a burden, however, and Dimitrov, despite occasional forays into the upper echelons of the ATP rankings, could never consistently deliver results. He dropped down to as low as 40th in the world in mid-2016.

But he has bounced back strongly to enjoy the best season of his career this year, winning four titles in all, including his first Masters title in Cincinnati.

Something has clicked and Dimitrov, now 26, began the year by reaching the Australian Open semi-finals and this time, he has backed it up with the most consistent year of his career.

After qualifying for the ATP Finals for the first time, he swept through his round-robin group unbeaten, fought off a ferocious challenge from American Jack Sock in the semi-finals and the rest is history.

He will end the year as world No. 3 - behind only Rafael Nadal and Federer - but crucially, Dimitrov believes he is now ready for an assault on the Grand Slams.

"Right now, it's a great platform for me to build on for next year," he said.

"Of course, one of my main goals is to win a tournament, you know, a Grand Slam tournament. This has always been, again, a dream of mine. Now slowly, I think this thing is getting there.

"As I said, I need to be even more consistent, and in the same time, raise up my level on occasions like this. Obviously, this is a great, unbelievable achievement for me, yes. But, yeah, I just still have a lot to give."

Dimitrov has become only the second ATP Finals debutant to win the title since John McEnroe defeated Arthur Ashe in 1978.

Yet rewind two years and he was struggling to play three good points in a row, let alone challenge for the big titles.

Out of adversity, however, Dimitrov has finally realised what it takes to put the puzzle together.

"With the right mindset, right people, the right support, things happen," he said.

"Little by little, drop by drop, here I am."

REUTERS, AGENCE FRANCE-PRESSE