Vale will certainly be underdogs for the Loftus Road encounter but the manner of their 1-0 triumph against their fellow promotion hopefuls on Saturday will have boosted confidence ahead of the tie.
Summer signing Stuart Tomlinson was handed a surprise start in goal at Gigg Lane and will again be looking to hold onto the gloves amid fierce competition from last season's number one Chris Martin.
Midfielder Gary Roberts and striker Justin Richards were also handed their competitive debuts for the club, although the former could be battling it out with captain Tommy Fraser who was restricted to a place on the bench at the weekend due to a badly bruised shin.
Winger Lewis Haldane (ankle) and defender Ritchie Sutton (suspended) continue to miss out.
