His career has been blighted by a problem with his right knee which restricts his fitness regime to swimming and gym work, with minimal time on the training ground with team-mates.
He was last called up to the squad in March 2009, but with doubts over the fitness of first-choice central defenders Rio Ferdinand and John Terry, Redknapp said his man would be up to the task if called upon.
"He is so important. He makes a massive difference to us and a fantastic character to have around," he said.
"Imagine how good he would have been without the injury. He would have been unbelievable because he is at the top level now without training."
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