Roger Federer´s incredible stranglehold on the Wimbledon title now looks under more threat than ever before with the emergence of Rafael Nadal and Novak Djokovic.

And that´s something that totesport´s tennis punters have no doubt considered when perusing SW19´s outright market.

Federer took his incredible unbeaten grass court record to 59 matches in landing the Gerry Weber Open in Halle recently.

But it was events over at Queen´s Club in London  – the traditional warm-up for Wimbledon – where the performances of finalists Nadal and Djokovic really caught the eye.

Nadal´s 7-5, 6-4 semi-final win over perennial Wimbledon fancy Andy Roddick was particularly impressive and marks him out as a genuine title contender.

In last year´s brilliant Wimbledon final between Nadal and Federer the Spaniard showed that the gap between them on grass is narrowing despite coming second best then.

There is no doubt that Nadal is the king of clay – as demonstrated by the way he thrashed Federer in Paris – and one wonders how much of a psychological advantage that win will be when they next meet.

Australian Open champ Djokovic thrashed Lleyton Hewitt and David Naldandian at Queens to re-assert his grass court claims and can also hold genuine claims for a semi-final appearance at the very least.

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