Ulster v Biarritz: Ulster don't enjoy make-or-break games like this, but they do tend to excel when faced with stark choices that will result in clear-cut outcomes. It's a stubborn part of the team character.
Mark McCall's side, third in the pool behind second-placed Saracens and leaders Biarritz, have only nine points from their first four matches. That slow start to the competition means they must beat the French side tonight and earn a bonus point if they are to have any chance of making it through to the knock-out stages of the tournament. A total of 19 points is the target they have been forced to set for themselves with just two games remaining.
But the match will be as much about what the travelling side need as much as what the home side need, and that is a win that should be enough to see Biarritz into the qualification stage of the competition for the fourth year in a row. Their final match of the pool series is a home tie against Saracens, while Ulster meet Italian side Benetton Treviso.
However, the words travel and French were never meant to sit harmoniously in the same sentence, and Ulster have proved time and time again that Ravenhill Road, almost as much as Thomond Park, is a difficult place to earn a win.
In December 2002, Ulster won the Belfast leg 13-9, while the Thomas Lievremont-led side have won the other two meetings which were both in France, the last in October 2005 when they comfortably earned a 33-19 win.
What might trouble McCall this time out is the indifferent form of his side. Their Ravenhill Road defeat at the hands of Leinster just after Christmas in the Celtic League was followed by a 25-23 win over Glasgow last weekend, where once again David Humphreys was required to kick his team to victory.
As a result, five changes have been made to the side that started against Glasgow. Isaac Boss replaces Kieran Campbell as the starting scrumhalf, while Matt McCullough and Paul Steinmetz return from injury to take their places in the secondrow and centre respectively.
Rowan Frost and James Topping move to the bench and Andrew Trimble moves out to the wing from centre to accommodate Steinmetz.
Young Stephen Ferris also makes his first start at openside flanker, ahead of Neil McMillan.
Biarritz arrive with the usual collection of big names, and although flanker Serge Betson is named on the squad, the international will not begin the match. He has been recovering from a damaged cheekbone since October, but is included in the replacements.
Petru Balan is in the frontrow, with the team including other internationals secondrow Jerome Thion, openside flanker Imanol Harinordoquy, scrumhalf Dimitri Yachvili, centre Philippe Bidabe and fullback Nicolas Brusque.
On paper, they should win, but the question is how much fire they bring to Belfast. Their inability to "get up" for away games has always been an unknown with the French, and one of their consistent weaknesses.
"One does not have the right to just travel and win," said Brusque during the week. Knowing only too well the French frailty, Brusque continued: "All these matches are very important. Ulster have large mental and physical qualities, in particular on their home ground. We still have to raise our level of play if we want to qualify."
For the home side, Simon Best turns out with the red hand on his breast for the 100th time.
"It's a big ask to defeat Biarritz and possibly grab a bonus point," he said. "But we have had some big nights at Ravenhill in Europe over the past eight years and we will be looking for another one of those."
That's what could win it. Ulster know it. Biarritz know it, and the Ulster fans know it too.
ULSTER: B Cunningham; T Bowe, K Maggs, P Steinmetz, A Trimble; D Humphreys, I Boss; B Young, R Best, S Best (capt), J Harrison, M McCullough, N Best, S Ferris, R Wilson. Replacements: N Brady, J Fitzpatrick, R Frost, N McMillan, K Campbell, A Larkin, J Topping.
BIARRITZ OLYMPIQUE: N Brusque; J Gobelet, P Bidabe, F Aramburu, S Bobo; J Peyrelongue, D Yachvili; P Balan, B August, B Benoit, J Thion, D Couzinet, T Dusautoir, T Lievremont (capt), I Harinordoquy. Replacements: B Noirot, K Lealamanua, O Booyse, S Betsen, J Dupuy, D Lison, B Dambielle.
Referee: D Pearson (RFU).