Chiedozie Ogbene is unlikely to be available for Ireland's World Cup triple-header with Portugal, Azerbaijan and Serbia.
Ogbene's hamstring injury is a blow as Stephen Kenny viewed the former Cork City and Limerick player as a threat on the right side with his direct style and pace.
The Rotherham player pulled up injured in last weekend's game with Sheffield Wednesday and his boss Paul Warne has said he won't be right 'for a couple of weeks' which is badly-timed for Ireland.
Dundalk winger Michael Duffy is set to miss the final cut unless other injuries emerge before Kenny names his squad on Thursday.
Lilywhites boss Vinny Perth indicated last weekend that Duffy was in the reckoning and could miss an important league game in Waterford on September 3 as a consequence. Clubs are given provisional notification that a player is under consideration so they can prepare accordingly.
However, while Kenny is a massive admirer of the Derryman, it's understood that he is going to remain on standby when the final panel is named and will therefore be available for the Waterford encounter.
Aaron Connolly's return to action at Brighton, the availability of James McClean and Daryl Horgan and the ability of other attacking options that can play on the left side is expected to leave Duffy just outside the tent.
The squad announcement is also likely to come too soon for Callum O'Dowda who has returned to training with Bristol City after sustaining a shin injury on the opening day of the Championship campaign.
Like Duffy, Shamrock Rovers' Celtic bound defender Liam Scales is on the long list with the absence of Enda Stevens opening the door.
However, Kenny can turn to Ryan Manning while the versatile McClean, Matt Doherty and Dara O'Shea can play in left sided defensive roles depending on the preferred system. Scales may therefore also find himself waiting on a phone call.