The football presenter has questioned the 68-year-old's motives for leaving Queens Park Rangers.
Redknapp was in charge at Loftus Road for the majority of the current campaign but left the R's in early February, resigning without having taken a single away point all season and leaving the west London side firmly in the relegation zone.
The 68-year-old cited the need for double knee surgery as the main reason for his QPR exit but Keys has now questioned that claim.
The Redknapp issue has been raised again after the former Tottenham and West Ham boss gave an interview with the BBC claiming people wanted him out before he left QPR.
And Keys isn't at all impressed with the manner in which Redknapp has conducted himself in leaving the Loftus Road outfit and now coming out with what he sees as a different story.
So by his own admission 'Arry didn't leave QPR cause of sore knees. Why didn't he tell the truth at the time? No need to answer that.— Richard Keys (@richardajkeys) April 10, 2015
QPR have continued to struggle since Redknapp's departure but successor Chris Ramsey has taken several points away from home.
Crucially, the R's have built up a head of steam recently and have given themselves every chance of avoiding relegation should they continue to produce the goods.