Champions Cup permutations.
While many have been lamenting the slow decline of the Investec Champions Cup, this is the weekend when interest starts to pique.
The final round of pool games brings the usual permutations scramble as those involved work out what they need to qualify for the Round of 16, to secure home advantage, or in Leinster's case simply finish as high in the seedings as possible.
Along the weekend, the prospective Round of 16 match-ups get pieced together like a jigsaw. A bonus-point here or there can have implications for a handful of clubs.
The qualification process works as follows: The top four teams from each Champions Cup pool go through to the Round of 16, while the teams who finish fifth drop down to the Challenge Cup knockouts.
After qualification, the seedings are broken down in blocks of four. The four pool winners take the first four seeds, ranked by their points total. Up next are the teams who finish second in their groups, and they fill in seeds five through eight, and so on.
Leinster, Munster and Ulster all have something to play for across the weekend, as do Connacht in the Challenge Cup.
Here’s what the outlook is like for the four provinces this weekend.

Leinster (home v Bath, Saturday 5.30pm)
Already qualified for the next round, Leinster are in their usual position heading into the final round of the pool stage where they are simply jostling for position, and trying to lock in as high a seed as possible.
Leo Cullen’s side are unlikely to finish as the number one seed, which would require both Bordeaux and Toulouse to suffer surprise defeats. However, the number 2 seed would serve much the same purpose, and give them home advantage for as long as they remain in the competition until the final in Cardiff.
Coming into the weekend, Leinster are ranked second of the four pool leaders, ahead of Toulon on points difference. In order to keep that top two seeding, the province will need to match Toulon’s result, with the French side away to Sale Sharks on Sunday evening.
For example, if Leinster win without a bonus-point against Bath, then a bonus-point win for Toulon on Sunday would see them leapfrog the province in the rankings.
If Leinster pick up a bonus-point win, then Toulon would also need to score four tries in their victory, while they would also need to overturn whatever points difference exists between the sides by Sunday evening.
With La Rochelle three points behind Leinster, Ronan O’Gara’s side could climb above the province into first place in Pool 2 if Leinster lose to Bath and La Rochelle win away to Benetton.
Pool 2 fixtures
Clermont Auvergne v Bristol Bears - Saturday 3.15pm
Leinster v Bath - Saturday 5.30pm
Benetton v La Rochelle - Saturday 5.30pm
Munster (away v Northampton Saints, Saturday 3.15pm)
Munster have the widest range of possibilities coming into this weekend, with the chance of finishing anywhere from first to fifth in the pool still on the cards.
Starting at the top, a win of any kind against Northampton will see Munster finish either first or second in the pool, securing home advantage for the Round of 16.
If they can finish first, that would also give them a home quarter-final, should they advance. To finish in that top bracket, they would need to beat the Saints, and also match Saracens’ result against Castres on Sunday.
As things stand, Munster are ahead of Sarries by virtue of points difference, +29 to +28. With the English side at home to Castres, the advantage would appear to be with Saracens.

A draw would more than likely see Munster finish third or fourth in the pool, barring an unlikely scenario where Sarries and Castres also have a stalemate. Bonus-points could also change things here.
If Munster lose, then a bonus-point would be enough to make sure they qualify for the next round. That probably won’t be necessary however, with only a very specific set of results knocking them down to fifth place and the Challenge Cup.
The only way Munster can be eliminated is if they pick up zero match points against Northampton AND if Stade Francais beat the Bulls in Pretoria with a bonus-point, AND if both Saracens and Castres pick up match-points in London. Even then, there would need to be a points difference swing to be made up between the sides.
Fortunately for the province, with the Bulls and Stade kicking off early on Saturday, there’s a chance Munster’s qualification will be guaranteed by the time they get underway at Franklin's Gardens at 3.15pm.
Pool 3 fixtures
Bulls v Stade Francais - Saturday 1pm
Northampton Saints v Munster - Saturday 3.15pm
Saracens v Castres - Sunday 3.15pm
Pool 1 - Ulster (home v Exeter Chiefs, Friday 8pm)
A much more straightforward set of circumstances for Ulster fans, although that’s not necessarily a good thing.
Despite three heavy defeats, all is not lost for the province. A win against Exeter on Friday night will at least see Richie Murphy’s side slip down the trap-door to the Challenge Cup knockouts. A draw would also likely do the trick, provided they match any potential try-scoring bonus that the Chiefs come away with.
They can still scrape into the Champions Cup knockouts.
In order to do so, they would need the full five points at Kingspan Stadium, AND they would need the Sharks to lose heavily away to Bordeaux, and see a 57-point swing in the points difference.
Even if the Sharks get thumped in France, a try-scoring bonus for the South Africans would eliminate Ulster.
Pool 1 fixtures
Ulster v Exeter Chiefs - Friday, 8pm
Bordeaux-Begles v Sharks - Sunday 1pm
Toulouse v Leicester Tigers - Sunday 3.15pm
CHALLENGE CUP
Pool 1 - Connacht (away v Cardiff, Friday 8pm)
Things are pretty simple, Connacht fans.
Your team are already qualified, and already guaranteed to have home advantage for the Round of 16 and quarter-final – should they get there.
A win of any kind away to Cardiff on Friday night would be enough to finish as one of the top two seeds, ensuring home advantage all the way to a potential semi-final, while a bonus-point win will make them the number one seed.
Even a draw in Wales will ensure they finish as one of the top two seeds.
Pool 1 fixtures
Cardiff v Connacht - Friday 8pm
Lyon v Cheetahs - Saturday 5.30pm
Zebre v Perpignan - Sunday 3.15pm
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