Thread by @AIUnderPressure

With the #EPL returning this weekend, it's time for our look at one of the issues affecting #LFC this season: the effectiveness of our systemic press. We think this is a unique perspective using our in-house pressing data

First of all it's worth noting that there are no issues with the intensity or volume of our press. And the production from the press in attack (shots, XG, counter-attacks) has been very good. The issues are on the defensive side, pressers being bypassed and gaps in the chain.

The pressing system is primarily the front 6 with secondary contributions from the fullbacks. This season #LFC have taken a mainstay out of that system (Wijnaldum) while another has played much less (Firmino). The result has been some significant teething problems

This is the combined heatmap from the 2018 and 2019 seasons (all comps) showing pressing FAILS. A failed press is when the presser either gives away a free kick or is directly bypassed with a dribble or vertical pass.

Fails averaged 22 per match and were mostly across the opposition final 3rd. relatively few in defensive areas.
(Also note we don't collect any presses up to the edge of the D in our half)

Now look at the 15 games from this season (we don't collect League Cup). We average 32 per match (10 more) and the heatmap shows 2 new areas, in the right halfspace (black) and in front of the centre backs (blue)

A major consequence of this is how many shots our opponents are getting from our failed presses. 26 in 15 games this season! (for context, in 2019/20 we had 10 all season)

What's really interesting when you drill down into the data is how many of the most costly fails are coming from members of the back 4
The efficiency of our fullbacks is down 12 % points (84% 2018 & 2019, 72% current)). Our CB's are down 15 points (90% 2018 & 2019, 75% current)

These are the failed presses of our centre backs in 2018 and 2019 combined. 45 in total, just 2 leading to shots and most well inside the opposition half

Now this season. 20 fails in total, with 3 leading to shots (note: it looks like 4 shots but one was a group press of 2 players)

This is our full data for this season ordered by total fails. Only Mane & Salah are in line with previous seasons (Elliott also impressive). Every other player is between 7 and 15 percentage points lower

To summarise: LFC currently have a sub-optimal pressing system in the front 6. In our data, the pressing looks like 16/17 season when we were still in the learning phase under Klopp, a good level below 18/19 and 19/20

This is putting more pressure on the back 4 who are in turn being too aggressive and giving up a lot of chances to the opposition. Joel Matip already has 39 presses with 14 fails from centre back this season, a frankly ridiculous number.

If you enjoyed this thread, check out the last 25 minutes of our most recent pod where we cover this in depth

https://twitter.com/AnfieldIndex/status/1458944955704090637?s=20

One final chart for the stattos. This is the team level pressing efficiency for every match we've collected under Klopp. This is one reason why we say 21/22 is looking like 16/17.
control limits are +/- 2 standard deviations.