First post, long time lurker - Don't think there's a more fitting issue and time to hop into head first.
A lot of the time when people speak about the 'defence', they refer to the back 4 specifically. Not the goal keeper, not the midfielders, but the back 4. The back 4 (Moreno, Lovren, Klavan) are 'not good enough'. Why? Because they concede goals? Name me a CB or back 4 in the world who doesn't. Anyone who has watched football or analyses it to any extent SHOULD be able to understand that the goals we concede, are not simply down to having a 'defence' that isn't good enough. I find it strange that pundits and so called experts attribute our poor 'defence' to our back 4 so often, rarely mentioning anything else. Note, I'm not arguing that our back 4 are good enough, I'm simply arguing the fact that our poor 'defence' and goals conceded being blamed on the back 4 is being completely overstated.
Klopp's philosophy and style of football is what is causing us to concede goals. Whether his philosophy works in the EPL compared to the Bundesliga is for another discussion. But if last year is anything to go by, we did alright and if not for key players being injured or unavailable, we'd have done better - and these players weren't the defenders... Food for thought.
When you play this style of football, your defence begins up the field in the front 3. Firmino, Salah, Mane are the vital cogs in this system for defending. The midfield is just as important, and LEAST, the back 4. Pressuring the ball up the field so the opposition has no time to play the ball is the key to this style. They're forced to play risky passes into midfield to attempt to retain the ball (where our engines nick in and start the counter) or they play long and play against the odds. Defending in this system is quite basic if your forwards and midfielders do their job and do it well - See Arsenal game as an example. They had shit all to do.
Now, when it doesn't go right - ie. Man City/Watford - where we lose a player or any of the front 6 have a bad day or choose to slack off or not defend, we concede just as many goals as our 'sub-par' back 4 are responsible for. I've analysed the key moments/goals in both Watford and Man City games and find that the problem begins up the pitch. First goal against Watford - Firmino (a forward) doesn't contest the ball. 3rd goal - Gini loses concentration and doesn't clear the ball - Gini, looked to be struggling late in the game - he's a midfielder.
City first goal - Mane doesn't contest the clearance from Mignolet (he's offside yes), and gives Walker a free header back into midfield. Gini loses his 50/50 against Fernandinho (can argue it's a foul) and the first and really only one to react is Aguero. Can is caught ball watching the entire time and reacts far too slowly to the threat that is De Bruyne with time and space. He should've realised as soon as walker had a clear header that this was going to be a sequence of 50/50 contests and should've moved back into position. At this point, Klavan is marking 2 players (but could've stepped up) - so any of Moreno/Matip or Klavan himself could have done better. My point being - any of the forwards, midfield, or defence could have done more to prevent that goal throughout the entire sequence. The rest of the game is history as we've already gone down a player.
The 5-0 is not a reflection of our 'defence' or back 4. The back 4 far too often is blamed. Being 1 man down against that City side is game over. When you cannot press the likes of De Bruyne and Silva, coupled with wingbacks having little to no responsibility defensively, any back 4 in world football would have struggled to keep them out. Neither is the 3-3 or 4-2 against Hoffenheim a reflection. Every defender that plays the game is susceptible to mistakes. Our system and philosophy amplifies them when they rear their ugly heads.
The key is to have a solid and balanced front 6 who know their roles and responsibilities in both going forward and defending - When to press high, when to drop and become compact - and when, or when not to, 'switch off'. A solid defensive midfielder who protects the back 4 is the key we're lacking. Henderson is not a natural DM - his positional sense and tactical awareness is not at the level required. I find him ball watching far too often. Hopefully Keita will prove this.
With all this said, of course, it would be beneficial to have better, solid, consistent, reliable defenders. But replacing the entire backline will not guarantee an improvement in 'defending' or conceding goals. A leader who understand the ebb and flow of the game and has the ability to control it (whether a midfield general or a defender), improved tactical awareness (through training) to understand when to press and when to drop deeper is what will guarantee an improved defence.
