Having hit the glass ceiling of the semi-final stage for three seasons in a row, and seven times in total since Munster’s second and most recent Heineken Cup success in 2008, the prospect of a fourth consecutive visit to the last four looks extremely tough given the Pool 4 schedule also includes defending champions Saracens and Racing 92, the two clubs which knocked them out in those 2017-19 semis.

Not having first-choice fly-half Carbery for what appears the first two rounds at the very least following his return from Ireland’s World Cup campaign with an ankle injury will make that challenge even tougher, though both of Munster’s options at number 10, JJ Hanrahan and Tyler Bleyendaal, have started the PRO14 season strongly.

Yet it underlines van Graan’s desire to strengthen his squad with newly-minted World Cup-winning experience, South Africa centre Damian de Allende and lock RG Snyman on the verge of signing for Munster for next season.

Munster have reached an advanced stage in bringing the heavyweight Springbok duo to Limerick for 2020/21 and though van Graan yesterday said he would not declare their signings as done deals he outlined his ambition to build a squad capable of mixing it with the very best in Europe at the business end of the premier club competition.

“I wouldn’t want to speculate any further until there is confirmation of it,” van Graan said of his fellow South Africans. “Obviously we have spoken to both players and we have big dreams for the squad.

“If you want to win Europe and win the PRO14 you need 30 to 40 guys who can perform at any stage.”

Like the other provinces, Munster have dipped into their academy stocks across the first five rounds of the PRO14 season with a dozen frontline on Ireland duty at the World Cup in Japan.

Those players returned to the province on Monday and all but Carbery will be available for this Saturday’s PRO14 derby at home to Ulster, though not all will be used ahead of the European opener in west Wales.

They will have to wait longer for Carbery, who never looked comfortable in Japan following the ankle injury he suffered against Italy in pre-season on August 10.

“Joey is one of our star players,” van Graan said. “The 25 out of 25 that he kicked showed that last year when he was on the field he made a big difference to our play. He did some very special things.

“At the back end of last season we didn’t have him for the (Saracens) semi-final and he literally came back (for the PRO14 semi) against Leinster, played for 60 minutes and went into the national team, went to the World Cup that I am not going to comment on, but he came back to us now.

“He is going to be out for some time. We got to make sure he gets his strength back and we get that ankle fully functional.

“The effort JJ and Tyler have put into their fitness, into their kicking, into their game management has been phenomenal. That’s why you got to have depth in your squad. You can’t have only one guy in a position.

“From Joey’s point of view obviously he wants to play but his body is not right. We got to get that fixed right.” Van Graan would not be drawn on the price length of Carbery’s absence but he ruled surgery for the fly-half.

“I honestly can’t say because I don’t know. Because of the type of injury he is definitely not going to be back in the next few weeks I can tell you that.” Asjed whether thay meant this side of Christmas, the Munster boss said: “I hope so. I hope so. At this stage it is very difficult for the medical team to determine that.

“They are not going that route (surgery). Because he has had it for quite a while the most important thing now is Joey’s health now. He is a Munster player. He is under my watch now so we got to look after him. Get his ankle right. Make sure he is good.

“He is very important for the national team, I believe, for the future of Irish rugby.

“I am not the coach but I imagine Faz (Andy Farrell, Ireland’s new head coach) will look at him. For Munster he is a game winner, that’s why we got him, that’s why we want him on the pitch but we don’t want him to play for a week and get injured again.”