Ulster are sweating on a host of frontliners ahead of Friday night's URC clash with Munster at Kingspan Stadium.

Head coach Richie Murphy is counting the cost of a damaging opening two rounds in the Champions Cup, with over 100 points conceded against Top 14 giants Toulouse and Bordeaux Begles and an extended injury list.

Skipper Iain Henderson, new Ireland cap Cormac Izuchukwu, out-half Aidan Morgan and Ireland back row Nick Timoney, plus winger Werner Kok and utility half-back Nathan Doak are all being monitored after picking up injuries on Saturday.

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Also doubtful are Ben Carson and Stewart Moore, who were both injured the previous weekend in Toulouse.

In a welcome piece of good news for Murphy, John Cooney has resumed full training and is available for selection.

Meanwhile, Craig Casey will undergo knee surgery this week and is a big doubt for the start of the Six Nations.

Munster have confirmed that the in-form scrum-half, who was forced off in Friday's Champions Cup defeat in Castres, has suffered a meniscus injury.

Casey is definitely looking at over a month out of action, potentially more, and with Ireland hosting England in their championship opener on February 1 it is clear that the Limerick man is facing a race against time to be fit for that game.

Casey has performed well for Munster in recent weeks and finished the November series strongly after he was disappointed to be left out of Ireland's squad for the Autumn Series opener against New Zealand.

With Conor Murray still unavailable due to an elbow injury, Munster's interim head coach will turn to Paddy Patterson for Friday's URC clash against Ulster.

Munster are also waiting to see if their summer signing Thaakir Abrahams will have to go under the knife. The flying winger sustained a dislocated shoulder in the 16-14 defeat to Castres and, having only recently returned to action, is facing another spell on the sidelines.

South Africa second row Jean Kleyn is also seeing a specialist after suffering a thigh injury last week, while Liam Coombes underwent surgery last week after sustaining a chest muscle injury in AIL action earlier this month.

Prop Dian Bleuler is unavailable for Friday's trip to Belfast after failing his HIA in Castes and is following the return to play protocols.

But hooker Diarmuid Barron passed his HIA and will be monitored this week following a shoulder injury, with his availability to be determined later in the week.

Former captain Peter O'Mahony is in a similar position after suffering a calf contusion and he may be held back for the visit of Leinster to Thomond Park two days after Christmas.

Munster report that the following players are continuing to rehab: Seán O’Brien (leg), Diarmuid Kilgallen (wrist), Jeremy Loughman (hip), Josh Wycherley (neck), Mark Donnelly (ankle), Patrick Campbell (shoulder), Cian Hurley (knee), Edwin Edogbo (Achilles) and Roman Salanoa (knee).

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