Cook rates getting Toure as the best piece of business he ever did - and insists the Ivorian didn't leave Barcelona for the £200,000-a-week wages.
"Yaya Toure was the one player who became the catalyst for change at the football club," said Cook to the Sunday Mirror.
"He has become City's talisman. The popular perception is that we signed Robinho and Carlos Tevez to attract other players to the club.
"But both of those guys were in it for what they could get rather than what they could do for City.
"Yaya was different. He came and said, 'I'm going to make this club great'."
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