Henry the latest Irish casualty

Ireland were hit by a new injury blow when it was announced that loose forward Chris Henry is out of the rest of the Six Nations with a knee injury.

The 28-year-old Ulster stalwart - who has come on as a replacement in Ireland's two Six Nations game so far - has been replaced by Munster loose forward Tommy O'Donnell in the squad for this Sunday's match against Scotland at Murrayfield.

"Following an MRI scan today, it was confirmed to the Ireland medical team that back row Chris Henry suffered a cartilage tear to his right knee while playing last Friday," read a statement from the Irish Rugby Football Union (IRFU).

"The injury will require surgery and will rule Henry out of playing for approximately four weeks."

Centre Dave McSharry was also ruled out as he is still suffering from a niggling groin injury and been replaced by Ian Madigan in the 30-man squad which will be whittled down to 23 when coach Declan Kidney names the matchday 23 on Wednesday.

Both Scotland and Ireland are on two points, the Scots having beaten Italy last time out after losing to England and the Irish coming off a narrow loss to the English after beating last year's Grand Slam champions Wales.