Remember New Years Day, when Spurs ripped through the Chelsea defence five times? And that was with Nemanja Matic in the side.
The Serbian was not the only one in the Chelsea XI that day who looked like he had been up partying into 2015. But his jaded, hungover-looking performance was noted more than most.
Forget Diego Costa and Cesc Fabregas – Matic is the man Chelsea miss more than anyone else. And he just happens to be banned for Sunday's League Cup final.
Ignoring the controversy over the initial decision, and the failed appeal, the reality is he won't be there.
And while John Mikel Obi's sizeable Chelsea non-fan club will not rue the fact the Nigerian is also out through injury, that leaves the Blues with precisely no tried options to fit into that position in this team.
Matic is more than just a holding midfielder. He runs up, he runs down, he passes, he tackles.
He is as close to a total footballer as any in Chelsea's armoury. And, give or take Yaya Toure at his best (which he isn't right now), the same can be said of him across the Premier League.
The position he occupies is all the more vital in Chelsea's set-up because he provides the cover at centre half to allow the fullbacks to bomb upfield. There is an argument to suggest every one of Branislav Ivanovic's six goals this season owes at least some form of assist to Matic.
But, as we saw on New Years Day, when he goes missing it leaves Chelsea's defence very vulnerable.
So with Chelsea on a poor run of form, without Matic and his deputy, and about to face Harry Kane – a man Chelsea showed eight weeks back that they didn't have a clue how to handle – what are the options?
Well, if Mourinho does intend to finally get the first silverware of his return, the truth is they are few.
It seems unlikely Chelsea will shift their formation in a final (though it has, of course, happened before). So the question is simply one of who to place beside Fabregas.
Oscar is the most likely option – he can and has played there, though Mourinho has refused to try that in any depth with this present set of players, insisting his creative talents are too good.
But those creative talents seem to have gone AWOL of late, and there has never been greater clamour among supporters to ship him off to PSG for a hefty fee.
Ramires is another option – though, to be frank, there has to be a worry whether a player known for having plenty of 'run' in his legs has enough 'think' in his head to do what is quite a complex job. Ramires is also known for occasional lapses into incredible recklessness – something which is additionally risky in that position.
Willian is another long-shot – and possibly a good one, if only he can be drilled to maintain the sort of positional discipline that is likely to hamper all of his natural influences.
In different circumstances it might be gratifying to see young Nathan Ake tried there – he has experience in defensive midfield, and always displays discipline and composure when tried. But one suspects Mourinho will have little appetite to play that hand with so much at stake.
My guess is he will go with the cautious option – that means Oscar – and that Chelsea will be a lot more compact than in the shambolic and discipline-free visit to White Hart Lane.
That may not make for the best game to watch.
I do expect Chelsea to win, though not 5-1 as on the last occasion these two were at Wembley. I'm going 2-1, and possibly with an extra 30 minutes needed to decide that.