Former Leinster coach Matt Williams says Ireland head coach Andy Farrell is facing a 'very difficult selection dilemma' with hooker Dan Sheehan facing up to eight weeks on the sidelines.
Sheehan was forced off with a foot injury in Saturday's 29-10 win against England at the Aviva Stadium and didn't travel with the squad to Biarritz yesterday.
A six to eight-week layoff would mean the Leinster hooker would miss all of Ireland's pool games and his clubmate Ronan Kelleher has not yet featured in Ireland's warm-up matches.
"He's one of the best hookers in the world," Williams said on Monday Night Rugby after The Irish Independent reported on the extent of Sheehan's injury.
"It's very hard to take a player when you know that he may only make it back for the last pool game. It's a very difficult situation.
"With either the in-form team in the world in New Zealand or the hosts France awaiting in a quarter-final, Ireland needs every bounce of the ball to go their way.
"Having the best running hooker since Keith Wood out injured, it's far from an ideal situation."
With Kelleher still returning from a shoulder issue, Williams says Farrell will now need to decide whether it's worth naming an injured Sheehan in his 33-man squad.
"If you do include Sheehan, then you have to tell your other two hookers that will need to play in every pool game. One will have to start and the other on the bench in every game.
"It. is possible but any further injury then would be catastrophic. You're down to Cian Healy coming on as a hooker and Josh van der Flier throwing the ball.
"Josh did a fine job against Scotland but that's not something you want happening at a World Cup."
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