The English club lie third after a defeat at Racing 92 and a comprehensive home success over Ospreys, two points behind Racing and Munster, who are both unbeaten after two matches.

However, Saracens did come out on top the last time the two sides met, winning 32-16 in last season's Heineken Champions Cup semi-final in Coventry.

"Munster are one of those clubs that always get to the semi-final or final, always get out of their pool, so we know we are playing against one of the European powerhouses," McCall told the Irish Independent.

"There have been a few changes to their coaching staff this year. Stephen Larkham will obviously make a significant difference. Graham Rowntree is there as well, so they have brought some experienced coaches into the organisation.

"We had a tough semi-final against Munster last year and we know it’s going to be tougher this time round."

McCall insisted his side would not rest on their laurels as they bid to clinch a fourth Heineken Champions Cup in five seasons.

"We have a lengthy injury list and we need to manage the returning international players, but we have asked a lot of this group and they are resilient," McCall added.

"We need to think how we use our international players best, but we are not giving up on this competition at all. Of course, we are all bothered about it and we have some thinking to do. But I expect us to put out strong teams in this competition all the time.

"This team has been together for a long time. Relationships in the group are strong, relationships among the players and the staff are strong, and we all care about it."

Saracens director of rugby Mark McCall has described Saturday's opponents Munster Rugby as "a European powerhouse" as his side bid to leapfrog the Irish province in Heineken Champions Cup Pool 4.