Andy Farrell’s Ireland have paid a heavy price for last Friday’s convincing win over Argentina, as they have lost Sean Jansen to injury for the remainder of the Nations Championship while skipper Dan Sheehan faces a race to be fit to play the Springboks.

The six-try Irish blew away the Pumas 42-12 in a one-sided affair in Dublin, but a disappointing medical bulletin on Monday has highlighted how they are now very short at No.8 and also need another captain.

Capped twice on tour in July, Jansen made his home debut the other night but he has now become the latest casualty, joining fellow No.8s, skipper Caelan Doris and Jack Conan, on the sidelines.

The prognosis about Jansen’s knee potentially paves the way for a James McNabney debut on Saturday versus Fiji, but his absence will generate plenty of intrigue about who will play No.8 in the defining November 21 group match against the Springboks.

“12-day return-to-play protocol…”

Sheehan, whom Leinster successfully experimented with at No.8 in last month’s United Rugby Championship derby win over Munster, could possibly come into back-row contention versus the world champions if Farrell was willing to start regular sub Ronan Kelleher at hooker for Ireland.

However, that type of Sheehan-at-No.8 experiment at Test level is considered the longest of long shots, especially as the player is currently undergoing a 12-day return-to-play protocol following the concussion he sustained versus Argentina.

Sheehan was appointed Ireland’s captain for November in the absence of Doris, but a replacement will be needed for next weekend against the Fijians. Tadhg Beirne was handed the role back in July versus Japan in Newcastle. 

Farrell also has concerns over Rob Baloucoune and Josh van der Flier ahead of the Fijian clash but Bundee Aki, a late withdrawal from last Friday’s bench due to illness, is expected to train on Tuesday. A statement read: “The Ireland squad trained in the IRFU high performance centre on Monday ahead of Saturday night’s Nations Championship clash against Fiji at Aviva Stadium (kick-off 8:10pm).

“Dan Sheehan sustained a concussion during Ireland’s 42-12 victory over Argentina and the Ireland captain will undergo a 12-day return-to-play protocol. Sean Jansen (knee) has been ruled out of the remainder of the Nations Championship and will return to his province to continue his rehabilitation.

“Rob Baloucoune (cramp) and Josh van der Flier (ankle) will continue to be monitored over the coming days, with the management hopeful that they will both be available.

“Bundee Aki, who was a late withdrawal from the squad that defeated Argentina due to illness, is expected to resume full training on Tuesday. Gus McCarthy and David McCann will train with the squad this week.”

The Ireland team to face Fiji will be announced at 2pm on Thursday and ticket sales for Saturday’s game have passed the 45,500 mark, which is still some way off a sell-out crowd following last Friday’s below-capacity attendance against the Pumas.

Injury concerns haven’t been restricted to Farrell’s senior side, as three changes have been confirmed to the Ireland XV squad that will play Fiji A in Cork on November 20.

Tom Ahern (neck), Ethan McIlroy (thumb) and Michael Milne (ankle) have all been ruled out, with Fineen Wycherley, Todd Lawlor and Jeremy Loughman called up. That A-team match is part of a double-header involving the Ireland U20s against Scotland.