Stephen Kenny's side are 2-0 down from the first leg against Legia Warsaw and need two goals to give themselves a chance of qualifying for the next round.
Meanwhile the Champions League group stage is within touching distance for Brendan Rodgers and Celtic.
The Scottish title holders are 5-2 up going into the second leg of their play-off against Israel's Hapoel Be'er Sheva tonight.
In transfer news, reports say that Claudio Bravo is due to have a medical at Manchester City in the next 48 hours.
The fee for the Barcelona keeper is rumoured to be in the region of 17 million pounds.
The Spanish club recently announced that an agreement was in place with City to sell Bravo.