Tranmere boss Ronnie Moore is set to once more operate with a patched-up defence.
Rovers needed extra-time to see off Chesterfield 2-1 in Tuesday night's Capital One Cup tie and did so without centre-backs Ian Goodison, Mark McChrystal and Ash Taylor.
Taylor is available once more having returned from Wales Under-21 duty along with Jake Cassidy, but McChrystal remains out of action with a groin problem, while 39-year-old Goodison is set for a lengthy spell on the sidelines after learning he needs cartilage surgery.
Full-back Paul Black, a summer signing after being released by Oldham, must wait for his debut as he battles with a thigh injury and forward Adam McGurk is laid low with a similar complaint.
Former Rotherham winger Abdulai Bell-Baggie marked his Rovers debut from the bench with a dramatic 120th-minute winner in midweek and may come into Moore's thoughts for a starting berth.
Leyton Orient have an almost fully-fit squad.
Goalkeeper Jamie Jones is the only injury absentee and he is edging closer to a return to fitness following a shoulder problem.
Ryan Allsop will continue between the sticks after an impressive debut on Tuesday against Charlton, in which he saved a penalty in the shoot-out as Orient dumped the Championship new boys out of the Capital One Cup.
Allsop was one of six players to make their full debuts at The Valley along with Nathan Clarke, Lloyd James, Gary Sawyer, Mathieu Baudry and Anthony Griffith, while fellow summer signings Michael Symes and Ryan Brunt came off the bench.
Boss Russell Slade is hopeful the 120 minutes has not taken too much out of his new-look side and is unlikely to make changes.
