Chelsea play with 4-3-3 line up and Tottenham play with 4-4-2 line up. When Chelsea try to make game in set attacks, they look like this. Full backs take position in half-spaces, wingers go to touchlines and right and left centre midfielders support attacks from half-spaces. In this situation, I show you how Chelsea tried to make game from left but you can think it at the same way for right too. There is a difference between making game from right but I will explain it later when I have to explain. They usually tried to make game like this way.

Chelsea’s left stopper has the ball. When he passes to left back, the opponent’s right midfielder closes to left back to cover left back. But he doesn’t close to left back aggressively and the distance between him and left back was not less so left back has enough space to think and pass the ball. Right centre forward closes to Chelsea’s defensive midfielder because when the ball changes direction between Chelsea’s defense players, both centre forwards try not to let Chelsea’s defensive midfielder to take the ball comfortably. Chelsea’s left winger closes to left back from wing to be a pass option. The opponent’s right back closes to right but for now, he doesn’t take position closer to Chelsea’s left winger. He tries not to take position too far away from the defense line.

When the ball goes to left winger, the opponent’s right back closes to him but because right back wasn’t so close to him, right back didn’t cover him quickly and it gives to left winger a little bit extra time to do something with the ball. But as you see, the opponent has numerical advantage with 4 vs 2 against Chelsea in wing. So even left winger has some extra time and space to do something with the ball, his teammates are not close enough to him. So they can’t be effective with the ball and also when they lose the ball, they can’t take the ball back quickly because of numerical disadvantage.

Of course there are some reasons why Chelsea are in a disadvantageous situation. First of all, when the ball went to left winger from left back, the opponent’s right midfielder was more close to Chelsea’s left winger than left back. Because as I said before, he didn’t take position so close to left back when left back had the ball. This time, when both left back and the opponent’s right midfielder started to close to left winger, right midfielder was able to close to left winger more quickly than left back.
If we have to go to the second reason, as I said before, when left winger took the ball from left back, right back closed to him. And this time, Chelsea’s left centre midfielder tried to use left half-space and ran from the opponent’s right back’s behind. But the problem was, when he went forward, the opponent’s right stopper immediately closed to him. Because he wasn’t matching with any Chelsea player. So the opponent’s right stopper cover left centre midfielder.
But also, they could use it as a trap to change the game’s direction quickly. They had enough players to do that. Defensive midfielder was free because firstly, when the ball went to wing, the opponent’s right centre midfielder closed to wing and made a numerical advantage in wing. So the distance between him and defensive midfielder became more. The opponent’s left centre midfielder wasn’t taking position closer to defensive midfielder and when game’s direction changes, he takes position closer to defense line. So he doesn’t close to defensive midfielder either.
Secondly, when the ball went to wing, the opponent’s right centre forward wasn’t disturbing defensive midfielder anymore because basically, he didn’t follow defensive midfielder closely. Centre forwards were careful about covering defensive midfielder but like in this situation, not all the time. If the ball goes to the opponent’s own half side, centre forwards don’t take position closer to defensive midfielder as when the ball is in Chelsea’s own half side. Even if one of them closes to defensive midfielder, he doesn’t close to him quickly so even in worst situation for Chelsea, defensive midfielder finds enough space and time to be effective.
You can see that Chelsea’s centre forward wasn’t taking position closer to the wing when the ball wasn’t close there either. So if Chelsea’s players could change the game’s direction quickly, he could be useful to make game.
Now I have to explain the difference between making game from right and left. Chelsea didn’t try to change the game’s direction right to left as they changed left to right. Because Chelsea’s left back wasn’t supporting attacks like right back. He was taking position closer to defense line. It was an important factor and now, when I will explain to you how they change the game’s direction left to right, I will explain the reason that they didn’t do this for right to left either.
So left winger passes to free defensive midfielder. When defensive midfielder takes the ball, Chelsea’s right centre midfielder runs to the opponent’s defense line’s behind and pulls the opponent’s left back. Chelsea’s right winger could go to half-space with a diagonal run and be effective but the opponent’s left midfielder immediately covers left back’s space and right winger can’t use this space. Right back goes forward free as an extra player and Chelsea tried to use right back’s freedom.
And this is why Chelsea can’t change the game’s direction right to left. Left back doesn’t support attacks like right back. So from left, they don’t have an extra free player.

Right back could be effective with two ways: he can support the attack from half-space and before left centre midfielder covers him, he crosses the ball free. Or he supports the attack from wing and with right winger’s help, he crosses the ball from wing before the ball goes out. Firstly let’s have a look at what happens if he supports from half-space.

When right back supports the attack from half-space, he is completely free. The opponent’s left centre midfielder shifts to left to cover him but until he closes to right back, right back has enough time to be effective.
The space of right back is a great space for crossing. Right back is close enough to penalty box for crossing and he is not in pressure.
Now forwards have to show movement to right back into the penalty box. In this situation, right winger doesn’t try to run to the penalty box. The opponent’s left midfielder marks him closely. Right and left centre midfielders don’t show movement either. So centre forward and left winger have roles. Centre forward tries to escape from the stopper’s behind and left winger tries to escape from the opponent’s right back’s behind. But usually left winger doesn’t go to penalty box at the right time so even the ball would go to penalty box, before him, the opponent’s right back can take the ball.
If right back supports the attack from wing, this time different factors have roles. When I talk about supporting from wing, I am not talking about taking ball in only wing. I try to mean right back’s finding free space for crossing in wing. So we can keep looking at the new situation like previous situation’s continuation.

So right back takes the ball in half-space, passes to right winger and runs from wing. Chelsea’s defensive midfielder and right winger have important roles because they have to earn extra time to right back for his run from wing. And as you see, Chelsea’s left back closes to centre. So even if Chelsea lose the ball, they can take the ball back quickly with 3 defenders against 2 centre forwards.

After right back starts to run forward from wing, now the opponent’s left centre midfielder supports left midfielder. Now they are 2 vs 1 against right winger. But right back runs from wing free. Now in this situation, both don’t shift to wing to cover right back and stay.
So this time, right back can be free in wing and when he takes the ball in wing, he has a free space for crossing. And then centre forward and left winger do their movements to penalty box.