Dickson and Bolger in contention.The U's face Peterborough on Saturday, with enforced changes having to be made.
They limped off at Shrewsbury on twenty-four and eighty-six minutes respectively and have been ruled out of this weekend's fixture.
Manager Joe Dunne will be without Freddie Sears and David Wright, who both suffered hamstring injuries on Tuesday night.
Wright performed well as a makeshift centre half and Dunne moved quickly to bring in cover, snapping up Bolton's Cian Bolger on a month's loan.
Fellow defender Ryan Dickson is closer to a return, having recovered from the viral infection that has kept him out of the squad since the beginning of September.
U's: Walker, Cousins, Wilson, Spence, Okuonghae, Bolger, Dickson, Garbutt, Eastmond, Bond, Bean, Gilbey, Massey, Monakana, Szmodics, Sanderson, Morrison, Bonne, Lee, Ladapo
The likes of Sanchez Watt, Tom Eastman and Tosin Olufemi won't be available for the game against Darren Ferguson's side, but are expected to be back in training this coming week.
He has trained with the squad for the past two weeks and was an unused sub in Shropshire in midweek.