Chris Wilder admits losing Ian Morris to an horrific knee injury had an impact on Northampton as they lost 2-0 at Portsmouth.
Portsmouth secured a third home win of the week with a comfortable 2-0 triumph against Northampton.
Team news for Tuesday's League Two clash between Portsmouth and Northampton Town at Fratton Park.
Portsmouth have signed former Brighton goalkeeper Peter Brezovan on a non-contract basis.
Richard Money tipped Portsmouth to win League Two after seeing Cambridge fail to take advantage of their 10-man hosts in a 2-1 loss.
Cambridge failed to take advantage of 10-man Portsmouth as Ryan Taylor's strike and an own-goal gave the home side a 2-1 win.
Holders Peterborough United will start the defence of the Johnstone's Paint Trophy with a home game against Leyton Orient.
Team news for Saturday's League Two clash between Portsmouth and Cambridge United at Fratton Park.