GETTY Pat Cash doesn't fancy Rafael Nadal's chances in London

The first of those is the fact he's playing against Roger Federer - the man who has beaten him in the last five meetings.



The indoor hard-court is another fact against Nadal, who has struggled on the surface in the past.



Then Cash has far bigger concerns, including whether Nadal will even be fit enough to finish his round-robin group matches.



Nadal, 31, has a right knee injury which forced him out of the Paris Masters last week.



Cash told The Sunday Times: "Today on court at the London 02 Arena, he will be presented with the yearending world No1 trophy for the fourth time.

GETTY Roger Federer has beaten Rafael Nadal in their last five meetings

"Yet given the problems Nadal has suffered in the build-up to this year's tournament, does even the most committed Rafa fan expect him to break his duck this year?



"I certainly don't because I believe Federer is in the kind of mood and sufficiently rested to win again, and I even wonder how many round-robin group matches Nadal will actually complete.



"He admits he is not practising anywhere close to 100 per cent and for somebody who normally makes every ball really count, that is some admission.



"Indoor tennis simply does not suit the Nadal style. The ball does not bounce as high indoors and this does not favour big swings imparting lots of top-spin, which is of course the basis of Rafa's game.

GETTY Roger Federer and Rafael Nadal will battle it out at the O2

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