No way its 5 sets. If Federer feels it physically he will lose as im almost certain losing to Nadal will bother him way less than a 3rd defeat to Djokovic....in fact the Djokovic match at start of day may well determine outcome of Fedal.Not to bothered, probably Nadal though. However, hope they play a long physical match that lasts 5 hours! Bring the popcorn!