Devin Toner had surgery on his injured ankle this week. Photo by Brendan Moran/Sportsfile

Ireland look set to be without the services of Devin Toner for the remainder of the Six Nations and the experienced lock is a major doubt for Leinster's Champions Cup quarter-final agaisnt Ulster.

The 32-year-old Meathman, who has enjoyed an incredible injury-free run in recent years, underwent surgery on his injured ankle this week, Independent.ie understands.

Toner missed Leinster's European game against Wasps with the issue and suffered a recurrence against England last weekend, coming off with 20 minutes to play.

It remains to be seen if Toner can recover in time for his province's all-Irish last eight clash at the end of March - two weeks after the Six Nations ends.

If he doesn't make it the injury will have a knock-on effect for Leo Cullen's selection given the tournament rules that limit the number of overseas players in a match-day squad.

Scott Fardy will take over from Toner, meaning the coach must choose between Jamison Gibson-Park and James Lowe in the backs - a decision further complicated by Luke McGrath's knee injury. The scrum-half is out of the Six Nations, but due back before the game.

The injury has immediate ramifications for Ireland who have a number of second-row injuries to deal with.

Joe Schmidt has called on Connacht's Quinn Roux for tomorrow's clash with Scotland, with Ultan Dillane on the bench.

Tadhg Beirne could return for the round three meeting with Italy, but Iain Henderson is rated as an outside chance for the final two games against France and Wales.

Online Editors