Goalkeeper Gilks missed last weekend's 2-1 win over Millwall, their second triumph in three matches, because of a one-match suspension he collected after being sent off for deliberate handball in the defeat to Barnsley.
Caretaker boss Steve Thompson will have to decide whether to recall Gilks or stick with Mark Halstead, who made his first league start for the club at Bloomfield Road.
On-loan Aston Villa striker Nathan Delfouneso came off the bench to net a late winner against the Lions and is pushing for promotion to the starting line-up.
But defenders Ian Evatt (knee) and Bob Harris (toe) continue to be ruled out.
Thompson's temporary reign could come to an end after the Portman Road clash as reports have emerged that Paul Ince, the father of Tangerines star man Thomas Ince, is close to succeeding Michael Appleton.