Clarke worry for O's
Leyton Orient boss Russell Slade is waiting on defender Nathan Clarke ahead of their meeting with Shrewsbury.
Clarke suffered a head injury against Carlisle on the opening day, forcing him to miss Tuesday's Capital One Cup win over Coventry.
Should he fail a late assessment, fellow defender Elliot Omozusi is on standby to deputise again.
Burnley loanee Marvin Bartley still awaits his competitive debut while Kevin Lisbie is expectedto retain his place in attack after netting a brace against the Sky Blues.
New arrival Graham Burke is in line to make his Shrewsbury debut.
The Aston Villa forward signed for the Shrews on Thursday on loan until January and goes straight into contention as Graham Turner's side go in search of their first win of the new season.
Burke's arrival comes after striker John Marsden was ruled out for between six to eight weeks having broken a bone in his foot during Tuesday's Capital One Cup defeat to Bolton.
Centre-back Dave Winfield faces a similar spell on the sidelines with his hamstring injury while on-loan striker Akwasi Asante (hamstring) is also not quite ready.