The former Real Madrid midfielder is back to his best at Milan this season.
“I dreamt of wearing this shirt again and I hope to continue doing so for many more years,” the 31-year-old said.
“I missed the environment of [training base] Milanello and the history of this club. That is what I missed when I was in Madrid.
“I like hanging around Milanello, talking to those who work there and remaining in close contact with them.”