For those that do not follow football, last Saturday was a big footballing night. It was the European Champions League final game and by coincidence the two final teams for Europe were both from England: Chelsea and Manchester City and they played in Porto, Portugal. It was a thrilling game and was not without surprises biggest of which was the fact that Manchester City who have had a great run this past one year and recent couple of years failed to beat or even equal the score by their arch-rivals Chelsea at least on the night.
It was down to a single goal scored by the 21 year-old German player Kai Havertz who saw the net barely three minutes before the break. Prior to the match, it is reported that Chelsea’s new German manager Thomas Tuchel told his players: “We need a top performance, and we need to be at our best level. …. We can do it……” That was enough, coupled with probably great training and coaching prior to that, to make the team fearless, positive-spirited and energised. Their play in the game showed it abundantly clearly.
By restoring a towering Antonio Rudiger in central defence when the new manager arrived, he was clear about his mission at Chelsea – to make them air-tight in defence. That strategy paid big dividend on Saturday because for nearly 55 minutes, Manchester City failed to equalise the single goal from Chelsea. Chelsea was rock solid in defence.
As I watched the game especially in the second half, I marvelled at how confident and resolved Chelsea was especially in their pursuit to stop Manchester City from equalising. Nearly every Chelsea player was helping defend. They defended as a team and there was a bit of science to it. As a background, one technique used in military operations and now well adopted in cyber-security strategy is what is called ‘defence in depth.”
Defence in depth is a technique where you have several layers of defence. Sometimes it is explained using an onion. You peal off one layer before the next. In defence too, you have multiple layers of defence before your opponent can reach the ultimate target. The military strategists design their defence mechanisms using the multi-layer approach.
To illustrate better, let us look at fortified domestic security apparatus. You will have a brick wall. If robbers can deal with that, they will meet the electric wire on top. If they break that barrier, they will be welcomed by the guard who will then blow the alarm inviting Goardaworld or other rapid response team that may take five to 15 minutes. Meanwhile, the robbers will meet security dogs barking and trying to bite them. This delays them as rapid response team is approaching.
Once they deal with the dogs, they have to break a door into the house. If they achieve that, they have to now break the burglar bars, which are not easy at all. By this time, the residents will have heard all the noise from the breaking of doors and whistles and they will probably call neighbours and police rapid response. In fact, inside the house they might also have motion detectors, which will detect entry of robbers and the big bell will ring and so on. This is precisely how defence in depth works.
The functions of defence in depth are many. One of them is to simply make it nearly impossible to reach the target point due to the multiple and different types of defences at every next level. Secondly, it is meant to introduce a delay so that the opponent is delayed until the best defender is put into the right position to deal with the opponent. Thirdly, it is so that if one layer fails, the other type of defence is able to contain the opponent.
This is precisely the science that Chelsea deployed on Saturday – defence in depth, centred around their maestro N’golo Kante. When a Manchester City striker was approaching, one defender would counter while others behind him were accurately and strategically lined up, alert and ready to tackle if the primary defender failed or made a mistake. This is how Manchester City failed to equalise. Congratulations Chelsea!