O’Gara, 35, started Munster’s 22-17 defeat to Racing Metro on Saturday but he left the field after just 33 minutes in Paris after picking up the injury with the club confirming that further examination ensures he will not take part against the Scots.

“The news of Ronan O’Gara (hamstring) is not so good after having a scan today and it is expected that he will not be fit to take part in the game at the weekend,” read a club statement.

O’Gara was hoping to add to his 124 caps for Ireland in their autumn internationals, having come off the bench in all three of the summer Tests against New Zealand as well as all five of their RBS 6 Nations matches earlier this year.

There was better news for Declan Kidney however, with the news that Paul O’Connell completed his first 60 minutes since May, having been struck down with a knee injury.

O’Connell, 32, captained Ireland throughout the 2012 Six Nations and will be hoping to add to his 85 caps against South Africa on November 10 and Argentina two weeks later.