Redknapp, whose side drew 2-2 with the Trotters on Saturday, admits he had a real interest in signing Cahill in the summer.

But the central defender penned a new deal at the Reebok Stadium in August, which removed a buy-out clause, which curtailed any hope Redknapp had of landing the 23-year-old England hopeful.

"He is a terrific centre-half, a potential England centre-half," said Redknapp.

"He had a buy-out clause but he has signed a new contract so that's an end to that - whatever he was worth then, he will cost a lot more now.

"He is a proper centre-half. What I like about him is that he's game. He wants it. He can head it, he's strong, he has a great attitude and he wants to win. I have always liked him, always thought he was a good player."