SOMETIMES when it comes to the end of the season, you need a supercomputer to work out the various permutations.
After all, there are 11 different combinations of points at stake in each game, and usually the end-of-season judgments depend on more than one game. It is enough to drive said supercomputer to drink.
So there has to be some relief that for Glasgow tonight, the stakes are about as simple as they can be. Beat Munster in the Thomond Park cauldron and they have a decent chance of not only making the play-offs of the RaboDirect PRO12 but would also be in pole position to earn a home tie in the semi-final. Lose, and while the play-offs would still be in their own hands, they face the prospect of returning to Limerick or facing Leinster in Dublin in their attempt to reach their first final.
Glasgow have made the semi-finals in three of the four years since they were reintroduced, but each time ended up as the away team and duly lost. In fact no team has ever won an away semi-final in the PRO12 so for Glasgow what this game is about is the difference between another nearly season and giving themselves a concrete chance of triumph.
They have been here before, though. Last season it should have been even easier. They had just thrashed Munster at home when they travelled to Llanelli with four games to go and the top two beckoning, only to go down 29-6 in their worst performance of the second part of the season and miss out on second place by two points. They had, incidentally, also been thrashed 31-3 at Thomond Park before Christmas.
This time the make-or-break game is even tougher. Thomond Park is always difficult, Munster are riding a wave of confidence and self-belief after thrashing Toulouse in the Heineken Cup and though they have rested seven from that side, the core who helped cut the French giants down to size will play tonight. They have not lost at home all season.
"Munster do have a couple of big games to go, so you never know, but we know this would be a huge result for the club and a huge result in terms of finishing in the top four and potentially in the top two," said Gregor Townsend, the Glasgow head coach.
"It is a tough place to visit. Last year, we let ourselves down with our defence and were heavily beaten. As they showed last week, if you don't get your game right, they will make it very uncomfortable. Last week was a typical European game where one team gets on top and gets the crowd behind them. They were creative round the lineout drive, defensively they were spot on as well, but more than anything they really intimidated Toulouse with the intensity they played at. That is why they have been in the quarter or semi-finals of Europe for the last 10 years."
To get there, Townsend has tinkered with his team. Stuart Hogg is back from the playing ban he picked up for his red card in Cardiff but promptly tweaked back muscles and cannot make his comeback as hoped, leaving Peter Murchie holding the fort at full-back. Duncan Weir returns at fly-half to partner Chris Cusiter, who also captains the side, and Tommy Seymour on the wing to complete the back division. Townsend has gone for a physical pack, which means no spot for Al Kellock, who is slowly returning to action from injury, and a huge vote of confidence in Jonny Gray, the 20-year-old lock who was capped last autumn as a teenager.
"The game against them earlier was an intense affair," said Townsend. "We put a team together on form; it was a tough team to select. We have used more than 30 players in the last three games, so that shows the depth we have and some of the form we are carrying forward into this game."