But another youngster steps into U's squad.
Craig Eastmond and Drey Wright won't make the Capital One Cup First Round clash, due to ankle and knee injuries respectively.
Both started the league game against Oldham on Saturday but will play no part in the game at The Valley.
George Moncur and Dominic Vose replaced the duo at the weekend and could be possible replacements in the U's starting eleven in South London.
Dunne has also included another product of the U's Academy in his eighteen man squad, with Jack Curtis making the step up from the U21s.
The eighteen year old, an instrumental part of the youth team success last season, will add midfield options against the Championship side in the season's first cup tie for the U's.
U's: Walker, Lewington, Clohessy, Thompson, Eastman, Kent, Okuonghae, Gordon, Gilbey, Bean, Curtis, Moncur, Vose, Sears, Massey, Szmodics, Holman, Ibehre.