Last updated on .From the section Tennis

Rafael Nadal and Roger Federer have faced each other 40 times

Rafa or Roger?

The two tennis greats prepare to meet each other at Wimbledon for the first time since 2008 in Friday's semi-final.

But how much do you REALLY know about Rafael Nadal and Roger Federer - not just on the court, but off it?

Test yourselves here with a quick-fire quiz.

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