The Spain international believes his coach deserves recognition for his consoling words for the man he poked in the eye earlier this season, who underwent surgery on Tuesday
Vilanova underwent an operation on Tuesday morning to remove a tumour found on his parotid gland.
Hours later Mourinho, who infamously poked Vilanova in the eye during his side's 3-2 defeat in the second leg of the Spanish Supercopa at Camp Nou earlier this year, showed his concern for the Spaniard and wished him a good recovery.
"Mourinho's gesture is 10 out of 10 and hats off to him," Casillas said to Marca.com.
"I think sometimes people always like debate and have an opinion on certain things, but when I saw Mourinho's gesture I thought it was top-notch.
"It was really nice of him to wish Vilanova well and we all feel the same way. But, I think there will be some people who don't like it when Mourinho says these kind of things.
"In any case, hats off to Mourinho. He is someone I know very well and he says things because he feels that way."
Following Real Madrid's stellar 6-2 Champions League win over Dinamo Zagreb on Tuesday, La Liga action resumes for Mourinho and his side on Saturday, with a city derby against Atletico Madrid.
"It's a derby where everyone is watching and I am sure Atletico will want to play a good game," he said.
"I don't think we are favourites, but we all know that we are doing really well of late. Our aim is to take things one game at a time."
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