Dortmund have played with a back line of 3 non-stop since november.
https://www.transfermarkt.com/borussia-dortmund/spielplandatum/verein/16
Werner is bought to provide width and competition to the front three.
The truth is 4-2-3-1 used to be popular, it's not anymore. It's exactly the opposite of what you're saying. 4-2-3-1 doesn't have the same triangles in build up as 4-3-3 does, so it's much more preferred in a direct tactic like Bayern 2013 or Mourinho's Madrid.
I have to disagree with you. You are 100% wrong on all of you have written. I know, for some reason you like always to argue with me and act like a judge on every post here, which I don't pay attention. But, when you pretend to now everything, it is not right to write such a nonsense.
For several years Dortmund has adopted the 4-2-3-1 system, even when Dembele, Lewndowski and Mkhitaryan were playing there. You are right that since Nov.2019, they have tried 4-3-3, but it did not worked well for them, so they came back to their basic 4-2-3-1. Yesterday's derby Borusia - Bayern proved that I was right and you were wrong. And this time, I am going to go with details to back my words.
Home team (Borusia Dotmund played in 4-2-3-1 formation)
...................
Haland........................
Hazard......
Brandt.......
Guereiro
................. (Sancho - 45)..........................
............
Dahoud............
Delaney......
...........(Witzel-85)........... (Can-45)............
Hakimi......
Hummels......
Akinji......
Piszczek
............................................................ (Gotze-80)
...................................
Burki........................................
Visiting team (Bayern Munich played 4-2-3-1 formation as well)
...........................
Lewandowski...................
.......
Coman......
T.Muller.......
Gnabry.....
........(Perisic -73).......................... (Martinez - 87)......
...................
Goretzka..........
Kimmich...............
Davies.......
Alaba.........
Boateng.......
Pavard
......................................................(Hernandez-85)...........................
.....................................
Neuer...............................................
This 4-2-3-1 system Andersito is a basic system, which is
still in use from many top teams in Europe. That formation allows teams to flow very easily to 4-3-3, when in counter-attack are needed more people up front. Hazard, Guereiro and Jadon Sancho are players who can make that flow for Borusia. Coman, Perisic, Gnabry and Martinez are the ones for Bayern. The beauty of this formation is that allows you to change it several times during the game,without making any players substitutions
Using the 4-2-3-1 formation, Bayern Munich has recorded some of its most perstigious victories in 2019 and 2020.
Oct.01,2019 Tottenham - Bayern 2:7
Oct.22,2019 Olympiacos - Bayern 2:3
Feb.25, 2020 Chelsea - Bayern 0:3
The truth is that 4-2-3-1 is still very popular and is exactly what I was saying. And, based on the players we have, it can be very beneficiary for Setien to start using it.
............................Martinez...........................
Griezmann............. Messi................. Trincao
................... DCM..................... FDJ....................
Alba......... LCD.................Pique.......... Semedo
......................... MATS......................................
Having fast wingers like Griezmann, A.Fati, Trincao or Dembele will allow for very smooth transition from 4-2-3-1 to 4-3-3 when is needed. Again, all teams choose their formations based on the players they have. You guys have to understand one thing. Messi is no longer that magical right winger who was able to dribble between 4-5-6 defenders and score or find an open team-mate. We all know that he is player without any certain position on the field. And our system after Guardiola is .... just look for Messi.... just pass it to Messi...... just Messi, Messi, Messi. That won't work anymore. All top teams know very well our playing stile and are taking advantage of it. If Barcelona does not change it's playing system and style, we won't be able to get out of the hole, we are at the moment. That is what I had to tell you and all other that are still living in that tiki-taka Pep's system. Sooner you forget it, better.