With less than a week left of the Premier League season, it's beyond the point of squeaky bum time for both Swansea and Southampton fans. Two sides that have spent much of the last decade wowing fans with classy, elegant football have fallen off the rails this season, and it seems that one is destined for the Championship next term.
Tuesday night is about as big as it gets in terms of relegation battles, and you might go as far as saying that this upcoming tie is the biggest in Swansea's 106 year history - not to put any pressure on the team (though at this point, pressure is most probably at capacity levels already).
The weekend's defeat to Bournemouth really made things difficult for the Swans. A poor performance that summarises how they've been on the road this season (one win in their last 18 away from home), and as a result it's come right down to the wire when Southampton visit.
Here's the table as it stands:
Equal on points with Southampton, and seven behind on goal difference, a loss almost certainly dooms the club to relegation. And that goes both ways - Southampton's only remaining game after the Swans is against Manchester City, whereas Carlos Carvalhal's men host already relegated Stoke.
A win on Tuesday night will effectively decide the future of both sides - and a draw will take it down to the last day, where anything is possible.
but why is this such a big game? If you look back down the years, everyone has always pointed to that club defining win over Hull in 2003 as the focal point of importance - and it was. But in that sense, 'was' is the most important aspect there. It's all about relativity.
Swansea have spent the last seven seasons in the Premier League, and yes, they could go down, fix things, and go back up again. But who would want to risk that? We've all seen what's happened to Sunderland.
Swansea can't have that happen. For a long time, the club's base point of relevance was where the Swans stood against Cardiff. The little city that should really be called a town was always punching to try and overcome the might of their South Wales rivals. In the summer of 2011 they finally did it, and for the rest of the decade Cardiff have been irrelevant to the Swans.
The Bluebirds are now back in the Premier League and it would be truly devastating to sink below them after so many years of superiority in Wales.
Even if it's for one season, no one would be able to stomach being 'second best' in Wales again.
You can keep your TV rights and Match of the Day screen time - that doesn't matter. We're past the point of being star struck by the big teams, it's old news. Swansea just want (no, need) to stay better than Cardiff.
The idea of comparing the two clubs once again proves how the mighty have fallen, and it's this problem of why Tuesday is so imperative that Swansea get the three points
A few years ago, when Swans were playing the likes of Valencia and Napoli in Europe, nobody cared about Cardiff. They were forgotten about. Now, a Neil Warnock-led side threatens to be claim superiority to one that completely outplayed Arsenal not five months ago. It simply cannot happen.
And it's the exact reason why they must win against Southampton. No one wants to see the Saints go down, they've been deserving of their place in the league ever since their return, and relegation suits the club ill. But if it's a case of us or them, you know exactly who we all want to be playing in the Championship next season.
Fortunately, the club's home form, and the atmosphere that the fans create swings the balance in Swansea's favour. As much as we all hate being in this situation, there's no denying that the atmosphere that a relegation battles generates at the Liberty is unparalleled, and it sets the perfect benchmark to get a team going.
Last season the players rose to it, but they're yet to do it this term. Tuesday is make or break.