The goalkeeper told As that the close-season dramas engulfing Robinho had had a negative effect on his play.
"It's inevitable that the controversy that surrounded him has played a role in his performances on the pitch," he said.
"We players are not machines and when someone is the focus of so much talk it can affect them at a personal level. We must protect him."
Looking back at the 3-2 loss at the Mestalla in the Supercopa, the Spanish international said that he was a "little bit sad" at the result as Madrid "can't afford to concede three goals in 45 minutes.
"We need to refine and improve what we did wrong, but we're not worried as that was only the first official game and we're still in pre-season.
"But even so, if you lose games like this you go home annoyed.
"In the first half we had one chance yet still scored... but we will fight to overcome what is not a bad scoreline."
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