He says only Premier League clubs have the financial clout to take the 32-year-old.
Redknapp said: "It's difficult. It's only Premier League clubs who could afford to take him on his wages.
"Other clubs aren't going to put up that type of money. There isn't big money in this league wages-wise.
"If any of them want to take a thousand-per-cent drop in wages or something, they can, but you don't see too many doing that."
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