Munster lock Donnacha Ryan will miss Ireland's autumn internationals and is in a race against time to be fit for the 2015 Six Nations campaign after it was announced he is to undergo toe surgery.
The Tipperary-born forward is expected to be sidelined for up to six months and is set to miss at least 10 rounds of Munster's PRO12 league campaign, the pool stages of the Rugby Champions Cup as well as the Autumn series.
"Following a consultation with the specialist in London it has been confirmed that Donnacha Ryan will now require surgery on his toe," the Munster statement read.
"The Tipperary-lock injured his right foot in the PRO12 game against Treviso in March, and after extensive, conservative rehabilitation he has unfortunately been unable to rehabilitate the injury fully.
"He will now undergo surgery next week and is expected to be ruled out for the next four to six months."
Ryan missed most of Ireland's victorious Six Nations 2014 campaign through injury, failing to make an appearance despite forcing his way back into the training squads for the England and France clashes.
Munster head coach Anthony Foley said: "Donnacha has done everything that has been asked of him and we know it has been a tough time for him with the option of surgery available as a last resort.
"We are now at that point and we just want him to get through the next stage and back to full fitness."