Martinez said: "He is a player who everyone listens to and in the modern game that is a big start. When Samuel Eto'o says something people listen.
"He has done a lot of things in the game but the most impressive aspect is that he wants to achieve more. He is not done yet. And that is something which is rubbing off on the rest of the squad.
"From my point of view, that is really impressive. He is desperate to achieve more and help the team with the approach of being able to talk with anyone and being able to share his experience with anyone.
"But this was his choice. We value his talent immensely. Whatever people think it was a very important moment for us to get Samuel."
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