Jared Payne was forced to sit out Ireland training on Wednesday due to a bruised foot.
The centre's contribution to the team has been the subject of much debate following last weekend's win against Romania.
Despite the injury, it was thought the Ulster player was still in with a chance of playing against Italy on Sunday.
However, on Off the Ball on Wednesday night, Nathan Murphy reported that he spotted Payne on crutches at the Ireland team hotel, exacerbating fears about the player's availability.
— Off The Ball (@offtheball) September 30, 2015
Also speaking on Off the Ball, Keith Wood - who was critical of Payne as an attacking force on TV3 - said that if the centre does not play, he would be a major loss defensively for Ireland.
Ireland have consistently done well defensively with Jared Payne. If he's injured that's the biggest loss we have. Our security looks far more vulnerable.
He seems to be the most confident player [defensively].
Picture credit: Stephen McCarthy / SPORTSFILE