In the following sentence:
Federer, who could now drop to World No.3 should Andy Murray reach the final, was beaten 6-4 6-2 by the Spaniard.
Who was beaten by the Spaniard? Federer or Murray?
Federer refuses to blame back injury - CNN.com
Federer was beaten by Nadal. If Andy Murray now reaches the final, Federer will drop to number 3 in the world.
You can read the sentence like this:
Federer (who could now drop to World No.3 should Andy Murray reach the final) was beaten 6-4 6-2 by the Spaniard.
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