Rangers were dealt a blow this morning when it emerged that Carlos Cuellar was unlikely to feature in the crucial champions league qualifier against FBK Kaunas.
The Spanish defender missed the goalless first leg at Ibrox last Wednesday after suffering a calf injury in a friendly against Raith Rovers.
Manager Walter Smith had been hopeful of a quick recovery as Rangers bid to keep their European hopes alive.
But assistant boss Ally McCoist admitted Cuellar probably would not have a part to play despite travelling to Lithuania with the rest of the team this morning.
He said: 'I wouldn't have thought he would play.
'There has been a vast improvement with his calf but it looks as though the game has come too quickly for him.'
Rangers are likely to play Danish side Aalborg in the final qualifying round if they progress.
But there is also a real threat of crashing out of Europe completely unless they show a vast improvement tomorrow night.
McCoist added: 'It's a big test for us early in the season and it's a game that we need to get a result in if we want to play European football - it's as simple as that.
'The pressure is not a problem, we showed last season that we can handle the pressure when it comes to getting results.
'We had a superb run in Europe last season and we know what's at stake this time - so let's get on with it.'
Rangers suffered a 4-0 thrashing at the hands of Liverpool at the weekend but McCoist does not believe that confidence has been dented.
He added: 'It was only a friendly and it was against one of the best sides in Europe.
'These games are all about fitness and getting prepared for the big matches and this is certainly a big match for us.'