THE JIG IS almost up for Tiger Woods this afternoon. After over five years as the world’s top golfer, his time in the box seat will end this weekend.

US Open champion Graeme McDowell was the early first-round leader at the Andalucia Masters earlier after shooting a bogey-free 3-under 68, according to AP.

Martin Kaymer, who could replace Woods atop the rankings with a high finish at Valderrama, carded a 1-over 72. The 25-year-old can take over No. 1 from Woods by winning or finishing tied with no more than one other player for second.

But he said his main priority was the Race to Dubai, which he leads from second-placed McDowell by €995,561.

The Irishman finished with a measured four-foot putt on the 18th green for his third birdie of the round.

Even if the in-form Kaymer doesn’t manage a high-placed finish this weekend, however, Woods will still be dethroned because of the bizarre system of scoring which decides the world rankings.

The injured Lee Westwood – Kaymer’s rival for the accolade -  has played just one tournament since August (not including the Ryder Cup, which doesn’t count in this instance) because of a calf muscle injury and all appearances suggest that he won’t be seen back in action for at least another few weeks, if at all in 2010.

Writes the Irish Examiner’s Charlie Mulqueen from Valderamma this afternoon:

[A]ll appearances suggest that [Westwood] won’t be seen back in action for at least another few weeks, if at all in 2010. How long the Englishman will stay up there is another matter as Woods returns to action in the WGC-HSBC Champions event in Shanghai next week and will be all out to put the record straight.

In any event, nobody wants to see the issue decided in this most irregular fashion. Being the kind of guy he is, Westwood would also want to be out there competing and claim the honour on the golf course. That’s one good reason why the Valderrama galleries were wishing Kaymer on during the first round.

Follow his progress on The Score throughout the weekend.