Stefanos Tsitsipas believes he is "really close" to winning a first Grand Slam after celebrating the biggest title of his career at the ATP Finals in London.
The 21-year-old Greek came back from a set down to defeat Dominic Thiem in a thrilling season finale at the O2 Arena and become the youngest winner of the tournament in 18 years.
Tsitsipas, who last year won the Next Gen ATP Finals - a season-ending tournament for the best aged 21-and-under players, impressed with his composure and fearless attitude on debut to provide further confirmation of his burgeoning reputation.
Now a four-time winner on tour, the charismatic champion has set out his stall for his next objective after a season which started with a run to the semi-final of the Australian Open and saw him establish himself inside the world's top 10.
"I feel like my game is getting better over time, and I believe I'm really close on being crowned a Grand Slam champion," said Tsitsipas, who won just over £2m in prize money with his title.
"I know these are strong words that I say, but I do feel like I belong to be there.
"I'm competing against one of the best players in the world, and the amount of effort and the amount of work I put every day deserves to have an outcome like this."
The week-long season-ending tournament, which was being held in London for the penultimate time, saw the younger stars of the sport steal the limelight from Rafael Nadal, Novak Djokovic and Roger Federer.
Despite believing in his ability and that his time will come, Tsitsipas is keen to not create an unnecessary weight of expectation on his shoulders to rush his pursuit of a major.
"The thing is if I put myself in a state of mind that I need to win this Grand Slam now, it doesn't work this way," he added.
"Rafa said it in the past: I'm not playing to win the tournament; I'm playing to win every single match that I'm about to go and play. So that's how it works.
"You don't want to travel too much in the future when you play a tournament, because it's not always going to go the way you want it to go."
The performances of Tsitsipas, runner-up Thiem and defending champion Alexander Zverev, who was knocked out in the semi-finals, have built belief that the next generation of talent will continue to close the gap to the older guard in 2020.
Thiem: Mentally, the most brutal sport
Thiem described tennis as "probably mentally the most brutal sport" after succumbing at the end of a final which showcased the future of men's tennis.
The Austrian, who had never progressed past the round-robin stage on his previous three visits, produced a brand of tennis full of thrilling intensity which was matched by Tsitsipas' supreme athleticism.
Thiem, who was targeting a sixth title of the season, fought back from 4-1 down to level at 4-4 in the final set tiebreak but ultimately came up short in his own bid to claim the prestigious title.
"It's not the end of the world, because I always think back on some matches in the past, like also in the last weeks, and I won some really close matches like this today to even get myself to the situation to play these Finals," Thiem said.
"It's always going to be like that in tennis. That's why it's probably mentally the most brutal sport existing, because you can play such a great match and end up losing in the championship match.
"From that point of view, it's a very disappointing loss, very hard to digest."