Djokovic and Nadal set up prospect of final showdown in inaugural ATP Cup

• Serbia face Russia, Australia meet Spain in semi-finals• Nadal 'suffered a lot physically' in win against Belgium There is only so far any hero can carry his tribe. Yet after a weary Novak Djokovic and Serbia limped through the quarter-finals of the ATP Cup into Saturday's match against Russia, Rafael Nadal lost and won in the space of a few hours as Spain beat Belgium 2-1 to book an evening showdown with Australia. Neither will be easy. It is asking a lot for either the world No 1 or No 2...