Baggies assistant boss Michael Appleton claimed he would be 'very surprised' if Long has recovered from his knee injury in time for international duty.
Albion predicted Long would be sidelined for six weeks when he suffered the setback 12 days ago against Aston Villa in a challenge from Alan Hutton.
Crocked: Shane Long was injured in West Brom's game against Aston Villa
But that did not stop Ireland boss Giovanni Trapattoni from naming Long in his squad for the two-legged tie.
Appleton said: 'It is one of those injuries you really have to be cautious with.
'Shane is doing everything the physios are asking him to do. He is working hard on the bikes but has not done any impact stuff.
Blow: Long looks like missing out on Ireland's matches against Estonia
'I have seen players come back from injuries ahead of when they are expected to.
'But I would be very surprised if Shane is available for the Ireland game. He will have to make a massive recovery in the next week or so.'
The first leg of the play-off is in Tallinn on November 11 with the return in Dublin four days later.
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