Celtic should only consider Kieran Tierney switching positions if it is a temporary solution.

Celtic’s lack of depth in defence is a problem they need to address in the upcoming transfer windows if they are to really kick on as a club.
They may be dominant in Scotland, but in the Champions League they have been caught out, and have been stretched due to injuries.
A potential solution was highlighted earlier in the international break when Celtic’s Kieran Tierney was started by Scotland at centre-back against Holland.

Of course Tierney is supremely talented and it would be wrong to doubt him, but if Celtic tried to make him the solution to their centre-back deficiencies it would be a poor decision.

Celtic will have money to spend after qualifying for the Champions League group stages, and Europa League prize money is also up for grabs providing they clinch third place.
Putting Tierney at centre-back weakens them at left-back, and is the easy way out of their predicament.
Prior to the transfer window it may be a necessity if the squad is stretched, but once Celtic reach January they must spend money on a proven player capable of helping the team from day one, and let Tierney continue in his best position.
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