Colin Montgomerie's hopes of winning a record eighth Order of Merit title have been boosted by Retief Goosen's withdrawal from the Volvo Masters. The South African, who is 224,000 euros behind Montgomerie, has a groin injury and will miss next week's event.
Michael Campbell, who is around 150,000 euros adrift, is the only man who can beat Montgomerie but needs a top-five finish at Valderrama to stand a chance.
Montgomerie, 42, is chasing his first Order of Merit title since 1999.
The Scot can only be beaten if Campbell wins the Volvo Masters at Valderrama, while if the US Open winner comes second, Montgomerie would have to tie with him to regain the title.
If Campbell is third, fourth or fifth, Montgomerie's task is to finish eighth, 22nd or 54th respectively.
Montgomerie, who has finished first, third and eighth in his last three starts, is all but certain to be part of Europe's Ryder Cup team again, even with 10 months of the race still to go.