Having squeezed past Colchester United (1-0) and Bradford City (2-1) away from home there is no doubt that the O's are happy to be back at Brisbane Road against another Yorkshire outfit in Sheffield United for the Third Round of the FA Cup.
O's boss Martin Ling welcomes back Sean Thornton into the side to face the Blades; the former Sunderland midfielder was due to miss the third round tie due to a one match suspension after picking up two bookings in the 1-0 defeat at Colchester United on 28th December - however he served this suspension at Leicester City last weekend.
Possible O's Line-Up: Glenn Morris, Jason Demetriou, Tamika Mkandawire, Andrew Cave-Brown, Brian Saah, Stephen Purches, Sean Thornton, Adam Chambers, Adam Boyd, Sam Parkin, Ryan Jarvis.
Sheffield United head into this third round clash after coming head-to-head with possible fourth round opponents Norwich City - whilst the Blades must conquer in London the Canaries have it all to do again at Carrow Road when they take on Charlton Athletic after the pair drew 1-1 at the Valley.
Sheffield United travel to Orient having claimed points on the road in their previous seven outings; their fine ran began on 28th October 2008 when they drew 0-0 at Bristol City and since then have claimed points at; Barnsley (won 2-1), Charlton Athletic (won 5-2), Ipswich Town (drew 1-1), Nottingham Forest (won 1-0), Swansea City (drew 1-1) and Wolverhampton Wanderers (drew 1-1), picking up thirteen points in the process. The last time the Blades lost on their travels was a 1-0 defeat at Sheffield Wednesday.
Blades boss Kevin Blackwell will be without midfielder Gary Speed (back) and defender Ugo Ehiogu (Achilles) who are both out for the remainder of the season.
Its likely that changes will be made with Championship football deemed more important; but Kyle Walker (Northampton Town) and Keith Gillespie (Charlton Athletic) have been recalled from their loan spells and may feature at Brisbane Road.
Possible Blades Line-Up: Justin Haber, Sun Jihai, Chris Morgan, Kyle Walker, Gary Naysmith, Keith Gillespie, Nick Montgomery, Brian Howard, David Carney, Darius Henderson, Billy Sharp.