This is a post about what Pep's thinking. Read a professional analysts and it is interesting. It says
Cutting inside itself is not a bad thing in itself - if it is utilised properly. And very clearly it is a pattern of Pep's tactic plan because the same sequence of play repeated many times in all 3 pre-season games. Grealish is a bit too orthodox and he tried to repeat this pattern too much (when sometimes he can really shoot or make a different choice).
Step 1 Grealish picks up the ball from the left and run towards the box, cut in and attract as many defenders as possible to the left flank. As we see in the graph here. Importantly he needs to make sure Fabinho - who usually marks KDB - is out of play - it means Zone 14 is free.
Step 2 Pass to KDB who is in Zone 14. He now has 3 choices. Halaand (if he makes a run) Mahrez or shot by himself.
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Step 3 Thiago sees the danger and tracks back with great speed. With his pressure, KDB delays a bit and chooses Mahrez on the right side. Mahrez made a shot on target.
Halaand movement can be inproved here. He stayed behind on the far side. It was common when we played without a striker. Gundo and Bernado often wait here for the cross coming in because their are shot and without great pace. But for Halaand - he can choose to run in behind with his speed and then Mahrez can have 2 choices - shot by himself or slip to Halaand.
The sequence is very similar to what we saw in the opening goal vs Germany. Sterling started the cut in run from the right side. A difference is - the lack of overlapping from the opposite side.
Remember how Luke Shaw overlapped and made the cross in? If Walker overlaps Mahrez here, Mahrez will have 3 choices and overlapping Walker will be the best. Halaand will have a good chance to finish it with a low cross from Walker. It will be more threatening than Mahrez shot by himself because the goalkeeper needs to switch his attention twice.
However Walker arrives late - it is quite understandable because he has to take heavy defending responsibility in the back - and he is the more defensive fullback of the pair.
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This explains why Pep wants to buy a left back like Cucurella who can play as a left center back like Walker. Then the left full back can act as the "more defensive fullbacks of the pair" and release the right back (Cancelo or Walker) to be more attacking on a higher position - and arrives in time for Mahrez. It is needed especially facing team like Liverpool whose right winger carries the bigger threat. Imaging Cancelo overlaps Mahrez and put a cross in to find Halaand! Remember Halaand is left footed - a cross from right to find his feet - will be deadly.
The reason why a pair of inverted winger are needed here. The first ball carrier winger can attract more attention when cutting inside. The second "finisher" winger can have a bigger angle of shot to max the threat when he receives the ball (remember how many times Foden's shot from left flank slips past the far post? Natural winger has much less angle to shot).
Why Pep designed this pattern? Not focus on running in the space behind?
- One possible answer might be - having a pair of natural winger to running behind is more threatening but more risky. When all 3 forwards running behind, the midfielder will deliver a cross and it has a very high chance to be intercepted. Especially facing a team like Liverpool when their defenders are very tall and they are very good at counter attack. As we seen in this game after the subs came on, KDB's cross find Foden and resulted a goal. But Gundo's cross was intercepted and resulted in a very dangerous counter. In the end the defense was tired out by multiple round of attack and started to make silly errors - like the penalty, Bernado gave ball away, etc, and we still lost...
Then why we played with a pair of natural winger (Foden and Jesus) in the Home game vs Liverpool last season?
- Pep gambled in that game
- Our defensive players were much fitter than current situation and can deal with the risk of counter a little better.
It explains a lot why Pep is so eager to bring in more full backs. With out the reserve full backs available on the bench, it is not wise to speed up the game.