The Tottenham boss has revealed that King is booked in for an operation on December 23 - but is praying the problem sorts itself out without the need for surgery in the next 10 days.
The 30-year-old has not played since Spurs' 2-1 win at Fulham two months ago, but Redknapp said: 'Ledley is improving and we are hoping he might be back soon.
Setback: King has not played since suffering injury at Fulham in October
'We have got two options for Ledley - we have got a date for a lady to operate on him, she is available on the 23rd of this month so we have really got until then to make a decision.
'He is coming on well and if he feels OK we won't operate. But if it needs doing we will have to get him done before then.'
Redknapp will be grateful to have defensive reinforcements after failing to register a clean sheet in the Barclays Premier League since the start of the season.
Jonathan Woodgate is a long-term absentee at centre half and cannot play until January at the earliest, while Younes Kaboul and Michael Dawson have also been absentees.
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