With reports suggesting Julian Araujo has been ruled out for up to eight weeks with a thigh injury, Celtic fans are fearing their season could unravel.
Martin O'Neill's side currently sit third in the Scottish Premiership after a defeat at Dundee United, with Rangers two points ahead and leaders Hearts five points clear.
News of the severity of the injury to Araujo, who has not played since the recent Scottish Cup win at Ibrox, has served as another blow during the international break.
With Alistair Johnston still working his way back to fitness after five months out, how damaging could Araujo's absence be?
Anthony Ralston or Colby Donovan would be tasked with filling the void until Johnston is ready, the latter having started in Celtic's past two games.
So how does Araujo compare to Ralston and Donovan?
Because of the difference in minutes played between the trio, we have crunched the numbers on a per-90-minute basis.
On the ball, Araujo shoots twice as often as both Ralston and Donovan. The Mexican also averages more dribbles and touches in the opposition box.
The on-loan Bournemouth man also averages far more passes in the final third, which helps explain why he creates more chances.
Donovan crosses far more frequently, however, and creates roughly the same number of open-play opportunities as Araujo.
But what about the defensive side?
Donovan wins more duels and aerial duels, and he has a far better tackle success rate.
Those impressive defensive numbers from the 19-year-old have helped Celtic concede fewer goals on average when he has played compared with when Araujo or Ralston have featured.
