Rafael Nadal ends year as number one

The Spaniard, 27, won 7-6 (7-5) 7-6 (8-6) to secure a semi-final place and guarantee he cannot be overtaken by world number two Novak Djokovic.

It will be the third time Nadal - who called it "the perfect scenario" - has finished a year top of the rankings.

Tomas Berdych plays David Ferrer in the day's other Group A match at 20:00 GMT.

Nadal has admitted he doubted whether he would ever recapture his best form when he was forced out of the sport for over seven months with a serious knee injury.

Since returning in February, his results have been spectacular, Kazinform has learnt from BBC News.

He arrived in London with a career-best record of 72 wins and six losses for the year, 10 tournament victories and Grand Slam titles at the French and US Opens that took his tally of majors to 13 - four behind all-time leader Roger Federer.

"Today it was important to secure the number one at the end of the season," said Nadal.

"During all the season I said it's not my goal, but the real thing is after all the success I had, after all that happened last year, I felt I deserved to be there at the end of the season.

"It's one of the best things that I did in my career - to come back to number one after three seasons. That's very difficult in our sport, and after a very important injury.

"That's an emotional thing for me, for sure."

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