After Carl Robinson's shock decision to quit Hillsborough and move instead on loan to Walsall for the rest of the season, Turner is keen to extend Reddy's loan deal from the Black Cats.
"I think it would be foolhardy for us to lose another player at this stage of the season," Turner said.
"Michael has got better as the games have gone by. He was very influential at Derby on Saturday, in the own goal, the sending-off, and in the second half when he got brought down, which should have been another sending-off.
"He can also play on the right side, where we haven't used him yet."