Following his sending off against Norwich for two bookable offences, John Mackie will serve his one-match ban on Saturday. In his absence Alan Pardew may choose to switch from 3-5-2 to 4-4-2 due to a lack of centre-backs.
"The formation is something we'll have to look at. The 3-5-2 has worked really well for us, but John Mackie has been a big part of that so we'll have to wait and see," said Pards, speaking to Reading World.
The Royals usually line-up with Adie Williams, John Mackie and Matthew Upson as the central back three. With Adi Viveash on loan at Oxford and Adie Whitbread recuperating from a knee injury it leaves Reading with just two centre-backs.
If Pardew chooses to stick with his relatively successful 3-5-2 formation then either Graeme Murty or Phil Parkinson could play out of position in the centre of defence.
However, if 4-4-2 is the prefered option Nicky Shorey, dropped for the previous three games, could return to the team. Whilst on the wing Sammy Igoe would be in contention to get a game.
After scoring in last week's clash with Stoke Anthony Rougier will expect to retain his place in the starting line-up.
However, the same cannot be said for Jamie Cureton who has gone seven games without a goal. Nicky Forster, who looked sharp when he came on against Stoke last week, or Martin Butler, who scored a hat-trick for the reserves, could take his place in the side.
Meanwhile Grimsby will be missing Stacey Coldicott (groin), Stephen Kabba (back), Steve Chettle, Steve Livingstone (broken skull), Tony Gallimore (suspension) and player manager Paul Groves (calf).
Predicted Reading Line-Up: Hahnemann, Murty, Williams, Upson, Parkinson, Salako, Hughes, Watson, Newman, Butler, Rougier
Reading MAD Predict: A 1-0 win for the Royals courtsey of a goal from Graeme Murty.