by Andy Schooler, at The O2
Rafael Nadal admits he never thought it would be possible for him to end 2017 as the world number one.
The Spaniard enjoyed a fantastic comeback from injury this season, winning the French and US Open titles as he saw off arch rival Roger Federer to finish the year in top spot, something he guaranteed prior to the ongoing ATP Finals.
After being presented with the year-end number one trophy on court at The O2 in London on Sunday, Nadal said: "For me it's been a fantastic season, a very emotional one after all the things I have been going through the last couple of years in terms of injuries.
"To have this trophy with me again is something I never thought one year ago. It means a lot to me."
Nadal added that the likes of coaches Carlos Moya and uncle Toni Nadal had played a big part in ensure he could return to his previous heights.
"None of this would be possible without my family, my team, a lot are here but some are not," he said.
"I want to say many thanks to all of them for the support. There have been some tough moments but everybody kept believing that things like this are possible again without the work of them probably I would never be back where I am today."
Nadal is currently Sky Bet's 11/4 joint favourite with Federer to start the 2018 season with a bang by winning the Australian Open.
Federer, who opened the tournament with a straight-sets victory over Jack Sock just before Nadal received his trophy, insisted he had no regrets about not finishing the year in top spot - something which would still have been possible if he had played in the recent Paris Masters.
However, he opted to withdraw to stay in peak condition for the ATP Finals.
Asked about losing the race, Federer said: "He was better throughout the year. He played more tournaments. He was incredibly successful throughout. So, no, I don't have any regrets because I feel like in my stage of my competition, my age, either it comes to me or it doesn't.
"He had more, you know, gas left in the tank than I did. I couldn't play as much as I've wanted, or I overplayed anyway.
"My only regret was I would have loved to be in contention through the Montreal finals, Cincinnati, US Open. But things evaporated very quickly after he won the US Open.
"In some ways I'm happy he clinched it because he deserves it. And like this, I can focus on playing the tournament, and not having to talk about that at the same time.
"But, sure, I would have loved to be it, but you can't be it with that many tournaments, so it's no problem for me."