Could this be mind games from Djoko before the final? Doesn't say much for him as a person if he can only stay friends with Andy if he has no chance of beating him in a slam. Andy and Rafa are great friends but the friendship is left in the locker room when they are competing against each other. It would appear Djoko can't handle being beat by a friend in the big matches.
While I do think he's being totally honest, it's also true that finally he sees Andy as a real threat. He was pretty friendly at 2011 AO before the tournament started and he demolished Andy in straight sets there in the final. But now that Andy pushed him into the 5th in the same event this year, then beat him at the Olympics semi and even won the title; not to mention, the way Andy thrashed Federer in the final and was also almost 2 sets to love up over him at Wimbledon, he now sees him as real a threat as Federer and Nadal.
This though means that only Andy has a couple of really tough rounds ahead of him. Ferrer is no threat to Nole on hard and Berdych is no threat to Nole in the final, if he makes it, but if Andy makes the final, he'll be finally facing the toughest round in the tournament. Of course, strange things do happen and maybe Ferrer is more prepared this time but it all remains to be seen.