Sunday - Exeter Chiefs v Ulster, Sandy Park, 5.30pm – BT Sport
Ironically Ulster’s uncomfortable last campaign with Ruan Pienaar on their books reaches its definitive match, certainly if they lose, without their Springbok pilot.
After getting enough opportunities, Paul Marshall is no longer the automatic replacement for the recuperating Pienaar as former Belvedere College scrumhalf David Shanahan, overlooked by the Leinster Academy, brings his slight yet elusive frame into this European cauldron.
The game waits for no man. Not even Tommy Bowe. After weeks of shuffling the multiple back-field talent, Les Kiss goes with form selections as Louis Ludik continues his maurading season at fullback, Charles Piutau should keep causing panic from the right while captain Andrew Trimble takes up arms on the left wing. Jacob Stockdale, the brilliant under-20 international as Ireland reached the 2016 Junior World Cup, squeezes his 32-year-old rival off the bench and possibly out of Six Nations consideration.
High stakes everywhere you look.
Ulster may be without Pienaar and Bowe, essential figures in bygone days, but Rory Best will lead them in all but official title and have no fear about Chris Henry marshalling the troops in behind the Ireland captain.
Ulster showed a viciousness in their exchanges with the Scarlets last Friday, only missing out on a valuable away scalp due to poor officiating by Marius Mitrea. The Italian referee yellow carded Seán Reidy for a textbook tackle on a dipping Welsh scrumhalf before running under the uprights for a seven point sting.
So Ulster arrive at the seemingly impregnable Sandy Park, the Chiefs are third in the Premiership but out of European running, in a terrible mood. Victory is the only target as Reidy switches to number eight and Iain Henderson stays at blindside.
Achieve that simple goal and they can throw the entire weight of Ravenhill, sorry Kingspan Stadium, at Ian Madigan's Bordeaux-Begles next Saturday.
There are interesting subplots. Ian Whitten is sure to collide with fellow Ulster-bred inside centre Stuart McCloksey while Gareth Steenson has some unfinished business against his home team after missing that drop goal in October.
Kieran Treadwell is another who must deliver. English by birth but from an Irish mother, the 6ft 7ins 21-year-old lock has dislodged the seemingly departing Franco van der Merwe from the Ulster engine room. He looks the part. Now he must back up Kiss's big selection call.
Ulster can do this – because of Paddy Jackson; because of Piutau’s mesmeric skills; because Best and the rest should batter them over the gainline.
“It’s a must-win game,” said Ludik. “I think we owe the supporters a lot and we have to go out there and make them proud.”
Otherwise Belfast will be awfully flat next week. Otherwise the chance of four Irish provinces making the quarter-finals for the first time will remain a pipe dream. Otherwise the whole Kiss revolution will come under serious scrutiny.
No pressure. No excuses. Win at all cost. Exeter, and their Premiership dreams, should struggle to cope.
EXETER CHIEFS: P Dollman; J Nowell, M Campagnaro, I Whitten, O Woodburn; G Steenson, D Lewis; B Moon, L Cowan-Dickie, G Holmes; M Lees, J Hill; T Johnson, D Armand, T Waldrom. Replacements: J Yeandle, M Low, H Williams, D Dennis, K Horstmann, S Townsend, J Simmonds, O Devoto.
ULSTER: L Ludik; C Piutau, L Marshall, S McCloskey, A Trimble; P Jackson, D Shanahan; C Black, R Best, R Kane; K Treadwell, P Browne; I Henderson, C Henry, S Reidy. Replacements: J Andrew, A Warwick, J Simpson, F Van Der Merwe, C Ross, P Marshall, B Herron, J Stockdale.
Referee: Romain Poite (France).
Betting: Ulster 10/11 (-7 handicap).