|Champions League play-off second leg: Malmo v Celtic (agg 2-3)|
|Venue: Swedbank Stadion, Malmo Date: Tuesday, 25 August Kick-off: 19:45 BSTCoverage: Live commentary on BBC Radio Scotland, live text on BBC Sport website|
In Malmo, the weather that greeted Celtic on their arrival in the city could have been a symbol of the tie itself; rain and wind one minute, clear skies and sunshine the next. Unpredictable, in other words.
So much has been said in the preamble to Tuesday night. Their manager, Age Hareide, and a number of his players have engaged in trash-talking as if it was a boxing ring they were entering on Tuesday rather than the Swedbank Stadium.
The first leg, a tumultuous affair won 3-2 by Ronny Deila's men, was not an hour old when Hareide sunk the boot in.
After seeing Jo Inge Berget nab a second away goal five minutes into added time, Hareide went for the jugular, claiming that he had seen Celtic play recently and knew they didn't have the legs to last 90 minutes.
It was more of a concentration and nerve problem than a fitness issue, but Celtic's vulnerability late in games is undeniable. It's happened too often - three times this season alone as well as numerous times in Europe last season - for Deila to argue otherwise.
The point is, though, that Hareide's jibe could easily be used against himself.
Malmo in the closing stages of games this season? Hacken scored against them in the 78th minute at the weekend. Gothenburg scored against them in the 85th minute. Norrkoping struck in the 88th minute. Gefle got one with 15 minutes left earlier in the season. Before that, Kalmar got two against Malmo in the last 12 minutes and Elfsborg got one in the 90th minute.
Hareide pointed the finger at Celtic, but Celtic would have been within their rights to point a finger right back.
There are all sorts of peripheral and surreal issues going on. Pig-gate, for instance.
On Monday, Hareide denied that his goalkeeper, Johan Wiland, called Celtic players pigs in the aftermath of the first leg. In his media conference before the second leg, Hareide said that the whole pig thing was lost in translation.
It was another comical moment in the build-up to what will be a deadly serious game of football, a match that is at the very heart of both club's seasons, a £15m game, if not more.
If you strip away all the mind games, there are more salient things to consider. A week ago, Mikael Lustig was stretchered off the pitch at Celtic Park. His manager said later that Lustig "does not look well".
In that moment, we mentally wrote him out of contention for the return leg, but now, miraculously, he's deemed 50-50 to make it. He was at Glasgow Airport with his team-mates and appeared to be walking freely. Has Lustig recovered or is this the most wishful thinking from Deila?
The answer could be key, for the most likely alternative to Lustig is not one that many Celtic fans would want to consider for all that long - Efe Ambrose. Lustig is hardly flawless, but there is generally an air of security when he's there. When it's Ambrose, you really never know when things might go awry. Maybe never, but there is always a dread.
In fairness to Deila, he has surrounded himself with a positivity shield and no amount of negativity is able to permeate it. He's not worried about Malmo's two away goals because he thinks his team will score and win and progress. He is unshakeable on that. There's an awful lot riding on him being right.
Malmo will have two important players back from suspension - the Ghanaian midfielder, Enoch Kofi Adu, and their leading goalscorer, Markus Rosenberg. That's significantly more firepower from last Wednesday. Malmo scored four goals in the group stages of the Champions League last season and Rosenberg got three of them.
Having scored two in Glasgow, they're exuding confidence in their ability to score again on Tuesday. Here's where it gets really interesting. They conceded three and could have conceded more, so if Malmo are sure they can unlock Celtic then Celtic must be equally certain that they can unlock Malmo.
One of the routes is obvious - the sniping Leigh Griffiths. There's another. Celtic had their own issues in dealing with a delivery into their penalty area at the fag-end of the first leg, but a failure to deal with crosses is a recurring theme for Malmo.
They conceded a goal from a corner - the winner - against Hacken at the weekend. They conceded from a corner against Celtic when Nir Bitton scored. They conceded again when Griffiths, hardly a footballing lighthouse, put away a header for a 3-1 lead. Earlier this month, IFK Gothenburg won a penalty - and scored from it - when Malmo's Felipe Carvalho hand-balled from a corner.
There's been other chaos in that Malmo defence recently when decent crosses have been put in. It's an area of opportunity for Celtic.
The smart money says that both sides will score. Beyond that, it's on a knife edge. Celtic can progress to the mammon of the Celtic League if - and only if - they have discipline and concentration.
At 2-0 last week, they had a corner and piled all their big men forward. When the delivery came in, Lustig, Virgil van Dijk and Dedryck Boyata were all in or around the Malmo six-yard box. In all, Celtic had five players in the small patch of ground.
Then Malmo broke, Scott Brown gave the ball away and the retreating cavalry didn't have time to organise themselves, and properly survey the danger, before Berget lashed in his opening goal. That kind of frenzied pursuit of killer goals could destroy Celtic if it's repeated.
Amid the noise - and the Swedbank has a reputation for raucousness - Deila's team have to be ruthlessly dispassionate. If nirvana is to be found, focus is the watchword.