Counago picked up a groin injury on the first day of pre-season training in July but was fit enough to be an unused substitute during the 2-0 defeat at West Brom on Saturday and could even start at London Road.
Manager Roy Keane said: "Pablo has trained well and he will certainly be involved. He has looked half decent in training and he is a goal threat so he is in my plans."
Captain Gareth McAuley was dropped to the bench at the weekend but will travel after Keane dismissed reports of a bust up. He said: "Gareth has been fine. He is a good lad, a good professional. He was on the bench on Saturday and probably felt he was unlucky.
There has been no bust up with Gareth. He is a good bloke and I have a lot of time for Gareth."
There could also be recalls for Colin Healy and Damien Delaney who were both left out of the squad at the Hawthorns, while goalkeeper Richard Wright may be rested to allow new signing Arran Lee-Barrett to make his debut.
Keane will still be without Jaime Peters (ankle) and long-term absentees Luciano Civelli, Ben Thatcher and David Norris (all knee).