QPR's point came at a cost as Brazilian Julio Cesar tore a groin late in the first half.
Redknapp said: "He did his groin, he tore a groin. He's a good pro, I have been impressed with him as a boy. You can see why he has played at the very, very top and what he's done in the game.
"But he went off and then Rob made a great save when he came on, so we are lucky there, we have got two good keepers."