"That Rafa loses against Coric, no one could have expected. I was surprised," said Federer. "He should not be defeated by someone I have ever seen play."
"But that was not the Rafa we know," noted Federer.
Federer, whose match followed Nadal's in Basel, saw Rafa drop the first set but did not start warming up, expecting the Spaniard to turn things around. Nadal, however, was well below his usual level, having been diagnosed with appendicitis at Shanghai.
"I don't want to take anything away from Coric, he did wonderful," said Federer, "but so weak I almost never see Rafa."
Nadal came off the court to announce that he was withdrawing from the Paris Masters and the ATP World Tour Finals to undergo surgery and rehab his back, which he injured at the Australian Open. The world No. 3 chose to compete in Shanghai and Basel despite his condition, taking antibiotics to control the inflammation.
"I do not understand it completely, because I would never do it that way," said Federer. "That he played in Shanghai with antibiotics and pain, then also played here and now ends the season because he needs an operation. But only he knows how he feels."