Chelsea spent all evening in search of penalties – and even had two players sent off in demanding them – so it was bitterly ironic that they eventually did prevail, in one of the most extraordinary FA Cup ties of modern-times, from the spot, after extra-time and from a shoot-out.

And this was a very modern cup-tie. The spotlight will fall heavily on the VAR – Video Assistant Referee – system.

It comes into use for “clear and obvious” errors but that was the only thing clear and obvious in a raucous, chaotic third round replay that was eventually cruel on Norwich City, 13th in the Championship.

How and when was the ‘VAR’ system used? No-one could accuse referee Graham Scott of not being decisive as he waved away a series of desperate appeals.

He booked Pedro for a ‘dive’. He also booked substitute Alvaro Morata for going over too easily, and he then gave the furious striker a second yellow card for his vehement protests.