The Argentine striker hopes to make an impact at Upton Park, following in the footsteps of Tevez, who dramatically inspired West Ham to Premier League safety in 2006.
"Carlos is a fantastic player and a fantastic person," Zarate told the club's official website. "I don't think I can do the same as he did, but I hope I can become as big a favourite at this club as he was.
"I hope I will play good football and reach the highest possible level. I am very confident I am going to succeed here."
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