Just said in the Rooney thread, we need legs in Midfield for this one. Agree with the comments above that Gana, Davies and Benigime are the best bets in the squad at the moment.
But as already pointed out I'd be amazed if BFS is anything but conservative in his team selection. "Big game, experienced heads, proven performers etc...".
Others may disagree because it is the Derby and they would want to avoid a hiding, but in general the senior midfield combinations have been absolutely rubbish and failed to turn up in many games (never mind the big ones) this season. So there's little to suggest they'll offer anything different on Saturday. So why not be radical and roll the dice?