Venue: Club de Golf Valderrama Sotogrande, Cadiz, Spain Date: 28-31 October
Coverage: Leaderboard and reports on BBC Sport website and updates on BBC Radio 5 live; live on Sky Sports 3
Either Kaymer (left) or Westwood (right) will replace Woods (centre) as world number one
Germany's Martin Kaymer can replace Tiger Woods as world number one at this week's Andalucia Masters at Valderrama.
Kaymer, 25, will usurp Woods and top the rankings for the first time if he wins the event or finishes joint second with no more than one other player.
Whatever the result in Spain, Woods's 281-week reign will end because the American is not in action this week.
Should Kaymer not finish high enough, England's Lee Westwood will take top spot, despite not playing this week.
This is because the Englishman's average of ranking points gained over the past two years will go above Woods's on Monday.
"Lee is the best player in the world right now," Kaymer said of Ryder Cup team-mate Westwood, who has been struggling with a calf injury.
"He's had a lot of trouble these last few months and I'm pretty sure if he hadn't he'd be number one by now.
"We've both played fantastic golf this year. Who deserves to be number one more? It's difficult to say."
Kaymer would become only the second German to reach the world number one spot after Bernhard Langer's three-week stint at the top in 1986.
The feat would be just reward for winning four tournaments this year including his first major at the USPGA Championship in August.
"Things have changed unbelievably for me this year, everything has been positive," said Kaymer.
"I've put the work in over the last three, four years but everything has paid off very very fast it's true. I wasn't expecting it but I'll take it."
However, the German, who was also a member of the European team that regained the Ryder Cup from America last month at Celtic Manor, insists that topping the rankings is not currently one of his main priorities.
"Of course it is one of the goals I want to achieve in my career," he said. "But at the moment I am concentrating on trying to win the Race to Dubai."
Most weeks at world number one
Tiger Woods (USA) 623 weeks
Greg Norman (AUS) 331 weeks
Nick Faldo (ENG) 98 weeks
Seve Ballesteros (ESP) 61 weeks
Ian Woosnam (WAL) 50 weeks
Nick Price (ZIM) 44 weeks
Vijay Singh (FIJ) 32 weeks
Fred Couples (USA) 16 weeks
David Duval (USA) 15 weeks
Ernie Els (SA) 9 weeks
Bernhard Langer (GER) 3 weeks
Tom Lehman (USA) 1 week
Westwood has chosen not to play in Spain as he continues his recovery from from a calf injury and a bout of illness.
But he remains focused on his return to action at the WGC-HSBC Champions in Shanghai on 4 November.
"I rested my leg completely after the Alfred Dunhill and now it's the best it's felt in four months," said Westwood. "Now I'm really looking forward to coming back in China.
"I had my leg up in the air for a week and then started doing gym work. I've just made sure it's properly rested this time. Now, once I've shaken off a bit of flu, I'll be ready to practice."
Alvaro Quiros, who will tee up on home turf at Valderrama, was full of praise for Kaymer.
"Martin is an incredible player and we are very close friends," said the 27-year-old. "His mindset and his attitude on course are just perfect.
"His game is not spectacular, but his putting certainly is, at least for the last two years. He is living in a sweet moment and that reflects on his demeanour, on the way he walks."
Kaymer currently has a 995,561 euro lead over Ryder Cup team-mate Graeme McDowell of Northern Ireland in the Race to Dubai money list with five European Tour events remaining.
US Open champion McDowell is also competing for the 500,000 euro first prize at Valderrama.
However, even if Kaymer wins his fourth straight strokeplay event in Spain to add to the USPGA, Dutch Open and Dunhill Links titles, the Race to Dubai will not be settled until next month.
This is because three of the final four tournaments - in Shanghai, Singapore and Dubai - carry a winner's purse in excess of 700,000 euros.