Rafael Nadal will return to number one in the world rankings after his semi-final opponent Tomas Berdych retired injured at the China Open on Saturday, capping an astonishing comeback from injury for the 13-time Grand Slam champion.
The Spanish world number two only needed to make the final in Beijing to edge ahead of Novak Djokovic in the new rankings, which will be announced by the ATP on Monday.
Nadal, who last toped the rankings in July 2011, has enjoyed a remarkable season, returning from injury to dominate the hardcourt tournaments.
Nadal will overtake defending China Open champion Djokovic at the top of the rankings even if the Serb overcomes France's Richard Gasquet in his semi-final later Saturday and retains the title on Sunday.
Czech Berdych pulled out of his semi-final after receiving treatment for an injury with Nadal leading 4-2 in the first set.
Nadal, sidelined for the second half of last year with a knee injury, has finished the season as number one twice before, in 2008 and 2010, and is unbeaten since he crashed out of Wimbledon in the first round in June.
The 27-year-old, tipped to eclipse Roger Federer's record of 17 Grand Slam titles, has won 10 ATP World Tour titles in 2013.