But perhaps not, because the other explanation for the quiet is that Everton under Ancelotti are hard to grasp; they slip through your fingers as you seek to describe them. Back in September when they went top of the league with four wins from four, there was a strong narrative to hold: James Rodriguez the creator, Dominic Calvert-Lewin the goalscorer, and a possession team built on crosses into the box.

Everton cannot be described in these simple terms any more, and unlike West Ham with their solid block and their Rice-Soucek fulcrum, or Leicester City with their explosive Barnes-Maddison-Vardy image, it is difficult to pin Everton down. They have no archetypal goal. You can’t visualise a passage of play that represents their playing style.

In fact, Everton deployed different formations in each of their three consecutive wins going into this game. More than any other team in the division, Everton keep you guessing. It is Carlo Ancelotti’s biggest strength, and the reason why Thomas Tuchel – a reactive tactician who pours over opposition data - will be worried about Monday’s game.

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Everton's formation flexibility is a strength

Ancelotti is a tactician of broad strokes, a hands-off manager who is perceived as either trustful of his players or lacking control, depending on how well his team are doing. Both arguments have already played out at Everton this season.

At times they have been flat, lifeless, badly in need of someone who will grab the reins. At others, they have played with the fluidity and self-assurance that owes much to the manager’s deft touch.

Tactically, he has an eye for the right formation and the right line-up, his main strength being careful plate-spinning: as soon as a system begins to falter he changes it, and more often than not he gets it right.

Everton have gone through a 4-3-3, a 4-2-3-1, a 4-4-2, a 3-5-2, and a diamond 4-4-2 formation this season, and almost every time the switch came after a defeat. Some managers, like Tuchel, are great sculptures who chisel a precise work of art. Ancelotti is more of a potter, his delicate touches gradually forming the piece as the wheel spins.

While Ancelotti’s tactics aren’t so easily defined, we can nevertheless see some interesting patterns in their play recently, and the signs point to a positive result at Stamford Bridge.

How Everton can frustrate Chelsea