It came in the second half, when Frank Lampard’s side were very much in control and constantly on the attack, only to predictably prove themselves susceptible to a quick surge forward. Mohamed Salah broke at pace, for the kind of situation he’s become so accustomed to in his time during the Premier League.
It is also the kind of defensive situation Chelsea have become used to in their short time under Lampard.
The difference, however, was a crucial element Chelsea haven’t had enough of: N’Golo Kante.
It even led to a joke from Jurgen Klopp, given the player's recent injury issues: “Kante is always fit to play Liverpool!”
And he was certainly fit enough to catch up, and beat, Salah. Although the Egyptian was just eating up the open space in front of him in that ominous manner that usually preludes a precise finish, Kante got around him, nicked the ball and won it.
Danger averted. Again.
This might have been typical Kante, but it emphasises an untypical situation, and is now of far more importance than one missed opportunity.
It is because the way Chelsea play means they are going to offer up that specific opportunity a lot. It's already been repeatedly illustrated this season.
And there’s going to be a lot of onus on Kante to cut them out. It’s just as well he’s capable of it, but may have lead to a situation even he seemed incapable of.
It may well reflect how his importance to a team has actually only grown - and this isn’t even down the fact he is the only prime world-class player left after the departure of Eden Hazard. It is because he is so fundamental to Lampard’s entire tactical plan.
There is an argument that it would be impossible to properly apply without him.
Kante, after all, essentially represents the totality of his manager’s defensive plan too.
He is certainly the sole truly defensive part in a midfield shape, that - just like at Derby County - is inevitably going to give up a lot of space in behind due to the emphasis on high pressing.
Kante, however, is pretty much the perfect player to fill that space. He’s maybe the only player who can fill this space, or at least does it to that level.
His very presence just instantly solves so many problems.
That maybe even means that, relative to his team and how they play, he is now the most important player in the Premier League. Or at least the equal of Virgil van Dijk.
They are the only players who feel so uniquely crucial to their side’s approach, where it just wouldn’t work in the same way without them; where there is no possible alternative. They're that distinctive. That good.
Lampard’s approach has thereby already emphasised Kante’s qualities even more. That relentless running, harrying and ball-winning has somehow become even more important.
And there was even more to his game here, because that running similarly set a greater tempo for Chelsea in the second half. It wasn’t just that Kante was filling gaps, it was that he was forcing them in the opposition. The rest of the Chelsea team started to rise to his level. The pressing intensified. It was from that, and that improved spell, that he scored a deserved goal.
Even for Kante, though, it’s impossible to fill every gap. Chelsea still have problems at set-pieces, which basically lost them this game.
Without Kante, though, they could have lost by far more. He, more than anyone else, ensured they were still in it. That’s what Lampard insisted at half-time.
It was partly based on the persistence of Kante.
It means he may somehow have become even more important than ever.
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