Munster return to Stradey Park on Saturday, the scene of their Heineken Cup quarter-final exit last March, determined to gain a victory that would keep them on track to make the last-eight in this season's tournament.
Last time out in Europe, Munster were comfortable winners over a largely second string Clermont Auvergne side but know they need to gain some form on the road to make their mark in Pool 5.
Declan Kidney's men currently lie second in the pool standings, three points behind table toppers Wasps and a full six clear of bottom of the pile Llanelli, who leaked 81 points in their defeats last month to Clermont Auvergne and Wasps.
The Welshmen have so far failed to recapture the form which saw them make the semi-finals last season but Munster lock Mick O'Driscoll knows they will be no pushovers, especially on home turf and after last week's EDF Energy Cup win over Saracens.
"The Scarlets are a tough nut to crack, particularly at Stradey Park, and it's absolutely ludicrous to suggest they will throw in the towel because they lost the opening two games of the campaign," O'Driscoll told the Irish Examiner.
"Defeat is really not an option. We were very disappointed to have lost to Wasps by a single point in the first match - it was a game we could and should have won and gaining a bonus point wasn't really much consolation.
"Every game from then on is as important as a cup final. We've been in that situation before and, I suppose, that might hold us in good stead.
"More than anything, we will have to retain possession and make sure that we don't give Llanelli any clear-cut chances to counter attack.
"They're very good at that and they're a team with considerable scoring power. We will have to severely limit them if we're to come away with the required result."
Regarding Munster's chances of making the quarter-finals, O'Driscoll, who is set for his 42nd Heineken Cup appearance this weekend, views the trip to the Scarlets as a "make or break game."
"If we're beaten, we are still in with a shout, mathematically, of making the last-eight, but it would be a huge uphill struggle."
Munster boss Kidney is also expecting something of a backlash from the Scarlets as they chase their first win of the tournament.
"Llanelli are always a side that we would respect. They beat us in last year's competition at Stradey. Our record there over the years hasn't been great in both Magners League and Heineken Cup and we know that they're capable of putting 50 points on anybody on their day," Kidney conceded.
"They've lost their first two Heineken Cup games and won't want to go three on the trot. They're going to turn up alright."