Window Shopping: Per Possession and Two Bundesliga Left-Backs

While the January transfer window isn’t seen as the best time to buy players, many clubs will most likely still look to bring people in this winter.

To try and find some players I thought it’d be interesting to implement a per ‘possession’ way of normalising the numbers and seeing what interesting names pop up.

Recently on Twitter @MixedKnuts suggested that using per possession data is a better alternative than just per 90 numbers, while @thefutebolist implemented their own per possession system. Both of those tweets can be seen below:

To try and implement by own way of per possession I’ll use StrataBet’s key entry data.

StrataBet’s key entries records the first time a team crosses the 18-yard-line (all across the pitch, not just in the box) in an attack, as opposed to recording every entry should a team move the ball back and forth. More reading on StrataBet’s key entries and whether or not they’re useful can be found here and here, with @AnalysisRich and @donceno offering different viewpoints.

With this definition in mind, key entries could be used as a proxy for attacks. Measuring a players chances or chances created per key entry should judge how active they are when their team attacks, as opposed to judge per 90 minutes. If a team has less attacks/key entries, it’s not surprising the players of that team have less chances or chances created.

Using something as a proxy is never going to be a perfect method, but it provides another way of looking at players and trying to even out their actions independent of playing styles.

So, the two Bundesliga left-backs.

Philipp Max – 24- Augsburg

Yep, implementing this fancy new way of looking at players has led to me unearthing the man with the most assists in Europe’s top five leagues.

Philipp Max first came to my attention when looking at secondary assists with StrataBet data last season, while not necessarily creating lots of secondary chances, they tended to be of high quality.

This season he looks to have improved further, almost doubling his xA p90 of 0.263 last season with 0.511 p90 this season.

Going off the per possession numbers Max has the 11th most open play chances created per 100 key entries in the Bundesliga this season, as well as the 5th highest xA from open play per 100 key entries.

Including set pieces (I’m not sure if I should for per possession based stuff) sees him shoot up to having the highest xA and most chances created per 100 entries in Europe’s top five leagues this season.

This shouldn’t come as too much as a surprise given set piece taking is an area where he excels. Looking at the xG value of chances following one of his set pieces (primary or secondary assist) and he provides 0.242 xG p90 just from set pieces, the 8th most in Europe’s top five leagues.

You want an attacking left-back who can create in both open play and take great set pieces? Philipp Max could be the choice.

Who should be in for him?

At 24 and with these kind of numbers for a team outside of the top teams, it feels as though the answer should be everyone. One particular club where he could make a great addition is Manchester United.

United have struggled at left-back this season, while Luke Shaw has played recently and 32-year-old Ashley Young has had some good performances in the position, it is an area they may be looking to improve.

Given Jose Mourinho’s tendency to buy players over 6 foot they could also benefit from Max’s deliveries into the box, whether they’d be from open play or set pieces. Interestingly, Manchester United have had the 7th most corners per game this season, yet created the 3rd least chances from them (via

Below are a few clips (mostly crosses and set pieces) of Max so far this season:

Christian Gunter – 24 – Freiburg

The second Bundesliga left-back with impressive numbers, particularly when looking at per possession numbers, is Christian Gunter of Freiburg.

While a sizable portion of Max’s output comes from set pieces, almost all of Gunter’s output comes from open play. His chances created from open play per 100 key entries is the highest in the Bundesliga and 11th highest in Europe’s top five leagues.

He doesn’t perform as well looking at open play xA per 100 key entries, with the 13th highest xA per 100 key entries in the Bundesliga, but that’s still impressive for a defensive player. Only Philipp Max and Mitchell Weiser have a higher value.

Gunter highlights how you can find some interesting players when looking at per possession numbers. Some of his per 90 numbers are fairly impressive (0.186 xA p90 for a bottom half left-back seems good) but playing for a side that has the 2nd least key entries in the Bundesliga it’s going to be incredibly difficult for him to put up per 90 numbers that really stand out.

It seems strange to suggest a player with just 1 assist this season (albeit under performing his 3.16 xA) could be a great signing for an attacking/creative left-back, which could ultimately lead to him being undervalued.

Who should be in for him?

If the interest in Philipp Max is to be believed, Gunter could make a great replacement for him at Augsburg being the same age and creating more open play chances per 100 key entries this season. Although he wouldn’t replace the set piece taking abilities of Max.

Two alternative teams are Everton and Burnley.

Freiburg take the 2nd least passes in the final third per shot, so Gunter is no stranger to direct football – which will mean he should fit in under Sam Allardyce or Sean Dyche. Then it also seems both teams could use strengthening at left-back.

Both clubs are in a position where their primary left-backs (Leighton Baines and Stephen Ward) are aging, while Gunter seems like he’d be an upgrade on the two alternatives (Cuco Martina and Charlie Taylor).

Below are some clips of Gunter:


In the end, I didn’t find as many players as I would have liked with these per possession numbers. Although this is mostly as quite a few players who stand out for per possession numbers either don’t seem realistic moves in January or are on loan at a club.

Examples of loan players include Remy Cabella on loan at Saint Etienne, Munir and Alfonso Pedraza on loan at Deportivo Alaves and Marco D’Alessandro on loan at Benevento, while Espanyol’s Gerard Moreno has recently renewed his contract and Ihlas Bebou only joined Hannover in the summer.

The two graphs below show how these players stand out. Firstly xG and open play xA per 100 entries:

Click to Enlarge

From the above, also from Augsburg and Freiburg are Alfred Finnbogason and Nils Petersen who have great per entry numbers – impressing in both xG and xA.

Alassane Plea is another name that is in a good area for a mix of xG and xA and looks as though he could be a good replacement for Cedric Bakambu at Villareal, should the rumours be believed.

While there aren’t too many differences, the graph below shows the number of chances per 100 key entries. One name of note is Jonathan Viera.

Viera has really great numbers for chances created, while his xA p90 of 0.336 is also impressive for a struggling Las Palmas side.

Click to Enlarge

I most likely will revisit using key entries as a proxy for attacks/possessions in an attempt to find players, although it may not be until the summer window is back.

This article was written with the aid of StrataData, which is property of Stratagem Technologies. StrataData powers the StrataBet Sports Trading Platform, in addition to StrataBet Premium Recommendations.

Data up to date as of 23/12/2017



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