Andy Murray will hope to tighten his grip on the world number one ranking when he plays Marin Cilic at the ATP World Tour Finals on Monday.
The Briton, 29, will end the year at the top of the rankings if he wins the title at London’s O2 Arena.
Murray faces Croatia’s Cilic in his opening round-robin match at approximately 20:00 GMT.
“I just want to finish the year on a high note by playing well,” the Scot told BBC Sport.
“If I finish number one, that’s great, but that wasn’t a goal of mine a few months ago. I wanted to put myself in a position to hopefully get there at the beginning part of next year.”
Switzerland’s Stan Wawrinka plays Kei Nishikori of Japan in Monday’s first singles match at 14:00, live on BBC Two and the BBC Sport website.
Murray overtook Novak Djokovic at the top of the rankings last week and is locked in a battle with the Serb to see which of them ends the year as world number one.
Djokovic opened with a three-set win over Dominic Thiem on Sunday, and knows that two group-stage wins followed by a record sixth ATP Finals title would see him reclaim top spot.
However, Murray can deny Djokovic if the Scot wins the season finale for the first time.
“He said that it wasn’t a focus to be world number one this year,” said BBC Sport commentator Andrew Castle.
“But with the Wimbledon title and Olympic gold behind him, he perhaps reset himself after the US Open and just said, ‘It’s available and I’m going to go for it.’
“He basically won every single match for the last six weeks.”
‘Faster courts will mean shorter points’
By his own standards, Murray has a relatively mediocre 11-11 record in eight previous appearances at the ATP finale, but he arrives this year in as strong a position as ever.
He is on a 19-match winning streak, and took three days off following his Paris Masters win before practising on the newly speeded up O2 Arena last week.
“The court’s definitely a bit faster than it has been in the past, so that changes the way you play the matches a little bit,” said Murray.
“But I think that’s a positive thing. At the end of the year, when the players have played a lot of tennis, to play on the slowest court with really, really long rallies is tough, so it will shorten the points a bit and maybe make for some better tennis.”
Murray has enjoyed the best season of his career, but if he is to hold on to the number one spot he must come through the most difficult run of matches he has faced in terms of rankings.
The Briton will play world number three Wawrinka, number five Nishikori and number seven Cilic in the John McEnroe Group, with only two progressing to the semi-finals.
First up is Cilic, who beat Murray last time out in Cincinnati three months ago but has won just three of their 14 matches.
“He’s been on an amazing run these last few weeks, he’s going to be extremely motivated and he’s going to have the crowd on his side,” said Cilic.
“I just hope I’m going to continue with this good form I had the last few months.”