The veteran midfielder was signed in the summer from Inter Milan, and the Foxes boss thinks that the ex-Argentina international's experience with the likes of Real Madrid will be invaluable this term.
Pearson told Sky Sports News: "First thing is, he's here to play, he is not here just to put bums on seats. With a CV he has, he's here to give us balance in midfield.
"He brings a wealth of experience and his contribution has been nothing but positive.
"He will bring a wealth of know-how. We're well aware we wouldn't be able to sign him if he wasn't at the end of his career. As a player, he has my total backing and hopefully he'll play his part."
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