The R’s sit 19th on the table, eight points from safety with four matches remaining, and Redknapp has sent a dire warning to his club if they do happen to be pushed back down to the Championship.
"I think this is a good club but when people say 'well, they'll come straight back up next year', it will be very hard to do that. Don't kid yourselves," said Redknapp.
"Whatever happens, the Championship is a tough, demanding league and you need players that are ready and willing to play Monday, Tuesday or Wednesday and then Saturday.
"You need the right characters if you're going to get out of the division and that is something that will have to be looked at very carefully."