THE news that Celtic’s Kieran Tierney is going to miss tomorrow night’s Europa League clash with Valencia may not have been unexpected, but it is disappointing for Brendan Rodgers and his side nonetheless.

The prospect of the 21-year-old being flung into a match of such magnitude after a couple of months on the sidelines was always remote, so Rodgers has had plenty of time to mull over his alternative options for the left-back area, and with Emilio Izaguirre now being passed fit for the match after missing out against St Johnstone on Sunday with an ankle knock, there are a number of ways the Celtic manager could go.

The first of those would be to stick with his line-up from Sunday’s stroll at Celtic Park against St Johnstone, and once again deploy Jonny Hayes as an auxiliary full-back. The Irishman, to his credit, did well against the Saints considering his lack of first-team action, impressing going forward and setting up a goal for James Forrest with a good run.

Given that Valencia had scored 10 goals in their four games prior to their goalless draw with Real Sociedad at the weekend, the Celtic backline is likely to be kept a great deal busier than they were on Sunday though, and Hayes’s defensive capabilities – as willing and as honest a worker that he is – would be in danger of being exposed at this higher level.

So, does Rodgers throw Izaguirre back in? The Honduran has been competent enough when he has been forced to fill in for Tierney since the Scotland star picked up his injury, and I felt it was harsh on him to be shuffled out of the side that faced Rangers at Ibrox prior to the winter break, with Callum McGregor asked to fill in.

READ MORE: Brendan Rodgers reveals Kieran Tierney won't make Valencia game

That move proved to hinder Celtic in the midfield area, and lessons would surely have been learned that they cannot be without McGregor’s influence in the middle of the park, so there is little prospect of that move being repeated. But given that Rodgers didn’t appear to trust Izaguirre in such an important match, and sacrificed other areas of his team to avoid playing him, it might suggest that he would also be reluctant to play the 32-year-old in a similarly huge encounter.

Which leaves really only one other option, and the one that I have a hunch Rodgers may go for, in moving new arrival Jeremy Toljan over to left-back and bringing Mikael Lustig back into the right-hand side.

Toljan has played at left-back before for Borussia Dortmund and is equally comfortable on either side. Lustig is now 32 and someway short of his peak, but he is still a decent performer and his vast experience of playing in these huge European nights for Celtic, particularly on home turf, should tip the scales in the Swede’s favour.