They've been in worse pickles, it's true, and we seem to have been here before more times than we can remember, but Munster playing hosts to Gloucester in a baying Thomond bearpit is as good an occasion as Irish rugby or even the Heineken European Cup can throw up.
Munster wouldn't be Munster if they didn't do things the hard way and, not for the first time, their chances of making the quarter-finals for the sixth year in a row have been put on the line by an away defeat. Another defeat to the Cherry and Whites - England's form side over the last year and a half - would seriously jeopardise their chances of finding their holy grail in Twickenham come the end of May.
Victory would leave them well placed to advance, but to entertain hopes of a cherished home quarter-final Munster probably need to at least deny Gloucester a bonus point (win by more than seven points) and outscore them in tries, whatever about scoring a bonus point themselves. On last week's evidence, it's a tall order.
The Gloucester pack ate into the Munster lineout, played much more on the front foot, cleaned out ruck ball better, and with Duncan "Rocky" McRae and Henry Paul applying the width, asked many more questions than Munster did. Gloucester looked a class act, and in the circumstances it was a helluva damage limitation exercise.
Gloucester won't be in such a defensive mindset as last year and won't be a soft touch with the richly talented Paul having found his niche at centre.
Nor will Munster swing from the hip quite so fearlessly.
But history has taught us never to doubt Munster, and where better to revive themselves than in front of a capacity 12,000 at their Limerick citadel? Munster have won all 19 of their Cup matches at Thomond Park dating back to the 17-13 win over Swansea eight seasons ago. In the hour of need, their supporters get behind them that bit more.
For the 1,260 tickets made available to the general public, there were 9,000 written applications. Even the corporate lunchers will be in their seats well in advance. Not that simply turning up at Thomond Park will win it for Munster, and they'll know that better than anyone.
Nevertheless, there's an intangible aspect to home advantage in this competition, and nowhere more so than here. How do you measure it? Running that bit harder, tackling that bit stronger perhaps, not to mention the pressure on visiting players.
Take Ronan O'Gara's early up-and-under last week. Might Jon Goodridge have caught the same ball in Thomond? Would Rob Henderson have charged up that bit quicker and contested it in the air? A whole game could hinge on one such incident. The ebb and flow of psychic energy, as Murray Mexted calls it.
Then there's the tangible stuff, beginning with the Munster lineout. Apparently the first two lost throws last week were the result of a mix-up between "Lanzarote calls" (from the pre-Christmas Irish camp) and their own.
In this, as in much else, Munster will assuredly benefit from last week's run-out after the Christmas hiatus. Frankie Sheahan's darts will surely fly better this time, and the forwards will hit the rucks far more clinically. Nobody beats Munster twice? We'll see, but certainly it's rare they play two bad games in a row, collectively or individually.
David Wallace will surely take on more ball, while Peter Stringer and O'Gara, in their 39th European Cup match together, will hardly play as distractedly as last week. It would be typical of O'Gara to have a big game today, and he's usually the best barometer of Munster's well being.
However, not alone will Munster need to do a whole lot more with the ball than just a procession of one-off runners and recycling ad nauseam, they'll have to apply more pressure, especially on messrs McRae and Paul.
Therein, perhaps, lies the rub.
Well though they defended out wide, and unstinting though their tackling was, Munster probably gave the Gloucester playmakers too much space. And McRae stands so deep he's hard to get at.
But despite his belated post-match apology to O'Gara last week for that salvo of punches on the Lions tour, one ventures Rocky will know he's not among friends today. Different ball game to last week alright.
MUNSTER : S Payne; J Kelly, M Mullins, R Henderson, A Horgan; R O'Gara, P Stringer; M Horan, F Sheahan, J Hayes, D O'Callaghan, P O'Connell, J Williams (capt), D Wallace, A Foley. Replacements: J Blaney, G McIlwham, D Pusey, S Keogh, E Reddan, J Staunton, J Holland.
GLOUCESTER: J Goodridge; M Garvey, T Fanolua, H Paul, J Simpson-Daniel; D McRae, A Gomarsall; T Woodman, C Fortey, A Deacon, A Brown, M Cornwell, J Boer, J Paramore, P Buxton. Replacements: C Collins, P Vickery, R Roncero, A Eustace, J Forrester, A Page, R Todd.
Referee: Joel Jutge (France).
Previous meetings: 2002-3 - Gloucester 35 Munster 16, Munster 33 Gloucester 6. 2003-4 - Gloucester 22 Munster 11.
Formguide: Munster - 18-17 v Bourgoin (away), 51-0 v Benetton Treviso (home), 11-22 v Gloucester (away). Gloucester - 33-12 v Benetton Treviso (away), 49-13 v Bourgoin (home), 22-11 v Munster (home).
Leading scorers: Gloucester - Henry Paul 54. Munster - Ronan O'Gara 55.
Leading try scorers: Gloucester - James Simpson-Daniel 4, Adam Eustace, Junior Paramore 2 each. Munster - Anthony Foley, Jason Holland 2 each.
Betting (Paddy Power): 1/4 Munster, 22/1 draw, 11/4 Gloucester. Handicap odds (= Gloucester +9pts) 10/11 Munster, 20/1 Draw, 10/11 Gloucester.
Forecast: Munster to win.