Lock: Tim Swinson (Scotland)
The Glasgow lock is set to miss Scotland’s Six Nations campaign after being ruled out for at least four months with a hand injury in November.
Flanker: Sam Warburton (Wales)
The Wales flanker, who has not played a match since captaining the British and Irish Lions to a Test series draw in Auckland last July, is almost certain to miss the remainder of the season after undergoing “proactive” knee surgery.
Flanker: Sean O’Brien (Ireland)
The back-rower is set to miss the opening rounds of this year’s Six Nations following a minor operation on his hip. Leinster confirmed today that the 30-year-old flanker had undergone a small procedure after seeing a specialist this week to address some tightness in his hip.
Number Eight: Taulupe Faletau (Wales)
Faletau is out of the Six Nations after suffering a tear to his knee. The Wales No 8 was cleared out a ruck aggressively by Mathieu Bastareaud in Bath’s defeat by Toulon in December– and now he will be out for three to four months. What aggravates matters is that he has injured the same left knee twice before in the last year.