Using data to find Leeds United a potential left back

Victor Orta will be working hard over the summer transfer window to make sure that he fills the positions and gets the players that manager Marcelo Bielsa wants. The main position and arguably the most important to fill this window is left back. Leeds have been linked with a number of left backs already and as Alioski is still undecided as to whether or not he will be staying, the importance of getting it right is crucial. As it is still early on in the transfer window, I thought it would be interesting to use data and the eye test to come up with two potential options for Leeds, one an ideal player and one a wildcard. All data will be taken from Wyscout and to ensure that IU didn’t have too many names showing up I included the following filters:  

  • Age 27 or under: Leeds already have a number of players that are approaching their 30’s so for a squad building purpose, players about to reach their peak years or those who have room to develop would preferred. Leeds don’t need short term options, they need someone who can play for a number of years at the highest level. 
  • 1000 minutes or more: Playing consistently and playing often is important. It also allows us to have a bigger sample size and therefore make more accurate decisions. 
  • Playing in the following leagues: Premier League, Ligue 1, Bundesliga, Serie A, La Liga, Belgium first division A, Liga Nos, Eredivisie and the Championship. These leagues were picked based on the quality and the likelihood of players being able to get work permits. Also all of these leagues have had a number of successful transfers. 
  • Players already linked with or playing for a major club: Those playing for a team like Man City for example won’t be joining Leeds so it would be pointless to include them. Also for the purpose of keeping this interesting and fun, I’ve left out the likes of Perraud, Sosa and Galan. 

I have tried to narrow down the metrics that I used to the ones that I feel are the most relevant to left backs and to a Marcelo Bielsa system. First up, defensive metrics. 

Defensive Duels vs Defensive Duels Won %

Casper De Norre of OH Leuven is the most active defender making 10.75 defensive duels per 90 but has a relatively low success rate. Noah Katterbach of Koln has the largest success levels in terms of winning his defensive duels but isn’t that active. Steffen Schäfer, Tyrick Mitchell and Reinildo Mandava all show up well in both volume and success rate. Next up we look at tackles and interceptions, these have already been possession adjusted.

PAdj Sliding Tackles vs PAdj Interceptions 

Jeff Hardeveld of Heracles is managing a massive 11.1 PAdj interceptions per 90 whilst also being quite an active tackler. Gijs Smal of FC Twente is the most active tackler along with Anderlecht’s Bogdan Mykhaylichenko. Bensebaini, Mittelstädt, Velkovski and Paulo Otávio all show up well in both departments. It is worth noting on all defensive stats that the player’s team and style will effect their numbers which is why for the final process I took a look at clips to see if the stats truly paint the right picture. Now moving onto how the players perform when under pressure and when looking to progress the ball, both important aspects of a Bielsa full back.

Dribbling vs Successful Dribbles %

In terms of dribbling, Gabriel Gudmundsson of Groningen is miles clear of the rest in terms of frequency at 9.01 dribbles per 90 with a pretty impressive success rate of 60.92%. He is followed by Ruben Vinagre who is on loan at Famalicão from Wolves. Gijs Smal has the best success rate but is only attempting 1.13 dribbles per 90. Witi, Ngonda, Kayembe and Vitinho impress both in dribbles attempted and in success rate. Dribbling is important when the full backs are pressured in both their own half and in the opposing half. Being able to beat the press as well as taking on the opposition in advance areas are important aspects for the modern day full back. So is ball progression, whether it is via carries or via passes, which brings me onto my next section.

Progressive Runs vs Progressive Passes

We once again see Gudmundsson lead the way with progressive runs, which makes sense given how good of a dribbler he is. Morgan Fox of Stoke City and Nicolas Gavory of Standard Liège lead the way when it comes to progressive passing, with the former also impressing with progressive runs. Sobol, Mykhaylichenko and Kayembe all shine in both departments. Crossing is one of the most important attributes when it comes to full backs in the modern day but as a stat it can be quite difficult to evaluate which is why we will build on this in the next section. 

Crossing vs Crossing Accuracy %

As with the two previous sections, Gudmundsson is number one when it comes to crosses per 90; an impressive 5.8 with a slightly below average crosses accuracy which is understandable with such volume. Morgan Fox and Jannes Horn are the most accurate crossers of the ball but both are below the average when it comes to frequency. Rafe Soares, Ryan Sessegnon and Augustinsson all perform well putting in a high number of crosses whilst also being able to find a teammate. As previously mentioned, crossing is important but when measuring it a successful cross doesn’t necessarily mean a good one. For example, a player might find a team mate at the back post unmarked but not in a dangerous position, whereas another player might put in a whipped cross between the goalkeeper and defenders but a team mate doesn’t gamble. One is successful and the other isn’t. This is why it is important to see the quality of chances that the left backs in this data are creating, using xA (excepted assists) and passes into the penalty area as not all players cross the ball from wide areas to create chances.

xA Per 90 vs Passes to Penalty Area per 90

Benfica’s Spanish left back Alex Grimaldo put up an impressive 0.24 xA last season which are f-numbers that a lot of wide players don’t produce. Norwich City’s Xavi Guintilla made the most passes to the penalty from this data set, making 6.05 per 90 and he is followed by Gudmundsson. Augustinsson, Gijs Smal and Gavory top those who produce in both metrics. A large amount of teams in today’s game play with wing backs which can relieve some defensive duties and allow more attacking which is one of the reasons why a large amount of the same names are showing up. 

My two choices:

  • Gabriel Gudmundsson is my wild card pick
  • Paulo Otávio is my ideal pick

On the the above graphs, they are represented as follows:

Gabriel Gudmundsson- FC Groningen

Age: 22

Nationality: Sweden 

Height: 1.81cm 

Minutes played: 1738

Previous Clubs: Halmstads BK

A number of clubs in Europe’s top leagues are reportedly interested in Gudmundsson after an impressive season and with only one year left on his contract, he could well be available and at a good price. Having started his career playing a more attacking role as a wide player, it’s easy to see why he stands out so much in the attacking metrics assessed above. He’s an excellent dribbler and ball carrier, almost acting as a wide player. He has played both in a back four and back three this season and performed well in both. Defensively he is still learning as the stats show. He has performed below average in his defensive duels won (%), PAdj sliding tackles and PAdj interceptions but is competing in 8.44 defensive duels per 90. With full back being a new position for him he has a tendency to switch off but does have some natural defensive instincts. He shows willing and is quite a gritty defender in terms of not giving up and sticking to his task even if he initially fails to win the ball. A great example of this is shown below.

Attacking is of course where he performs much better. His ability to run past players with burst of speed and agility is impressive. It is also important that once he gets into these advanced positions that he provides quality, which he does. One of the most common crosses/passes we see from him is a low cross across the area. We see both his ability to knock the ball past players and this cross in the example below. 

His defensive position is of course the major concern, especially if he was to set up to a higher quality league, however, at 22 there is plenty of time left in his career to develop this side of his game. I do think coming in as a first choice would be a massive risk so potentially bringing him as a back up to a more experienced full back from whom he can learn the defensive side of the game would be the better option. This of course is only a brief summary and my initial impression from the clips that I’ve watched so there will be other areas of his game that he needs to work on. 

Paulo Otávio- Wolfsburg

Age: 26

Nationality: Brazil 

Height: 1.73cm 

Minutes played: 2442

Previous Clubs: Paysandu (loan), LASK Linz, FC Ingolstadt

Paulo Otávio has been at Wolfsburg for two seasons now after joining from FC Ingolstadt and this season he was among the best full backs in the league. Despite only being mentioned once in the above data, he performed above average in all metrics except successful dribbles and progressive passes, even then only just falling short. With him playing in the Bundesliga his pressures per 90 are available on and it is safe to say he’d fit in perfectly at Leeds. He put up 16.84 pressures per 90 which puts him in the 94th percentile across the top 5 leagues. For context, Stuart Dallas put up 15.50 pressures when playing at full back for Leeds last season. Unlike Gudmundsson, defensively Otávio is very impressive. Despite only being 5ft 8, he’s very strong and once he’s got his body between man and ball, it is hard for the opposition to take it from him. His anticipation and timing of a tackle or interception is second to none, as the example below shows. It was vital he read the danger and got his tackle spot on.

Whilst he’s not an elite dribbler for a full back, he’s certainly comfortable and capable when under pressure or when required to beat his man in advanced positions. What he does well is providing width and then carrying the ball into space where he can then look to find a team mate with a short pass or put crosses into the box. His crossing is relatively good, putting the ball into the danger corridor, as seen below. 

He’s not as active in forward areas as Alioski was last season but would provide a good base defensively for Leeds’ left wingers, whether that be Harrison, Raphinha or a new signing. The main concern would be his ability when playing out from the back as he does tend to go long when under pressure but this looks like a confidence issue not a lack of ability. If he’s encouraged to play through pressure, I think he is more than capable. 


The modern full back is arguably the most difficult position to play, with most teams wanting players that are both good going forward and defensively. Through using the data I have identified two options who probably are at opposite ends of the spectrum, however Otávio still offers plenty going forward. As I mentioned, these data searches are not extremely in-depth and do only scratch the surface but nonetheless helped me to identity what are, in my opinion, two good options. 

By Thomas Wilson

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s