Ulster have confirmed that Ireland winger Andrew Trimble is to miss the rest of the season with a toe injury.
The winger was instrumental in Ireland's Six Nations success in 2014, scoring three tries.
Trimble has been sidelined since October with the injury, but Ireland were hopeful that he could feature in the latter stages of this year's Six Nations.
However, that is no longer a possibility, but he should be back in time for pre-season and the World Cup later this year.
"Ulster and Ireland winger, Andrew Trimble, will miss the rest of this season following confirmation that he has suffered a reoccurrence of the toe injury that he sustained in October against Glasgow Warriors," read a statement on Ulster's website.
"He underwent surgery in London today and is expected to be out of rugby until the summer.
"It is anticipated that he will make a full recovery ahead of pre-season and the Rugby World Cup."
Trimble has made 57 appearances for Ireland, scoring 16 tries.