Rafael Nadal virtually assured year-end top ATP ranking

London: A hoped-for fight to the finish for the year-end number one ranking at next month's ATP World Tour Finals in London will likely be a coronation for Rafa Nadal, who is virtually guaranteed ending 2017 top of the pile.

Roger Federer's eighth Swiss Indoors title on Sunday reduced the points gap on the Spaniard to 1,460 points, but his subsequent withdrawal from this week's Paris Masters means Nadal is poised to finish top for the fourth time in his career.

With 1,500 points available in London for winning the title, having won all three round-robin matches, the 31-year-old Nadal needs to win just one round in Paris to put himself out of reach of the 19-times grand slam champion.

It is a far cry from last year when the year-end ranking was decided in the last match of the season at London`s O2 Arena when Andy Murray beat Novak Djokovic to seal it.

"My body is asking for a break," 36-year-old Federer, who beat Argentina's Juan Martin del Potro in Basel to claim his 95th career title, said of his decision to give up the chase of Nadal.

"Basel takes a lot out of me emotionally. I had five matches in six days. I feel sorry and sad for Paris.

"I'd like to be fully fit for London (the World Tour Finals) and for 2018.

"I did think about the ranking, but I`m so far back in the points race that it was almost out of the question."

Nadal, who shared this year's grand slam titles with Federer, winning a 10th French Open and third U.S. Open title while the Swiss took the Australian and Wimbledon titles, starts his Paris campaign against either German serve-and-volleyer Mischa Zverev or young South Korean Hyeon Chung.

Federer has finished the year as number one five times, one less than record-holder Pete Sampras.