Finding Marcos Alonso Replacement At Chelsea 2019/2020 – Data Analysis

Frank Lampard’s Chelsea have shown signs of growth and development in a season that was expected to be a write-off given the transfer ban.

Through his excellent man-management and integrating youth into the side, the Blues found themselves sitting in fourth place before the enforced suspension of the Premier League.

Looking ahead at the summer transfer window, Chelsea are in the market for a new left-back and goalkeeper after unconvincing performances from their current options.

Specifically at left-back, Marcos Alonso and Emerson have been underwhelming for parts of the season, forcing Lampard to switch Cesar Azpilicueta over to left-back once again.

Neither has shown enough to appease Lampard’s worries, especially given Chelsea’s defensive frailties this season.

Lampard typically employs the 4-3-3 and 4-2-3-1 as his primary systems of choice but has on occasion opted for the 3-4-3 formation that involves wing-backs.

Here is where Alonso has shone; however, Lampard has only used this system against the bigger sides.

Lampard will probably opt for the 4-2-3-1 for the next campaign.

His two central midfielders are much more possession-hungry, and the three attackers behind the striker tend to tuck inside.

In Jorginho and N’Golo Kante, Chelsea have a functional and effective duo with a mixture of passing, pace, and power between them.

The same can be said of Mateo Kovacic, Ruben Loftus-Cheek, and Ross Barkley when plugged in.

While Jorginho will attempt to create from deep, and two inside forwards will run the channels, it comes down to the full-backs to provide width and an alternative source of attack.

Given the importance of this position, it is imperative that Chelsea find the best option that fits Lampard’s style.

Through data analysis, we will aim to identify the best possible replacements for Alonso given that he is likely to be moved on with one year left on his contract and inability to play in a four-man back line.

We will later look to provide a tactical analysis on these players to analyse their play style and ability further.

For this analysis, we will filter our data to include players under the age of 24 who played at least 700 minutes across Europe’s top five leagues, as it is likely that Chelsea’s eventual find will originate from there.

We will use four comparison metrics to find our full-back of choice.

Given Alonso is the full-back to give way, we will need a player who is proficient at attacking but much more diligent when it comes to his defensive duties.

Alonso has a knack for scoring crucial goals, utilising his height, power, and ability to arrive in the box late.

But given that he’s an exception to the rule, we will focus on chance creation and progression as our key elements as Lampard will use them primarily as crossing outlets.

The two metrics I have chosen to use are crosses vs crosses accuracy % and progressive runs per 90 vs deep completion passes per 90 with Expected Assists (xA).

These two metrics should give us an all-around indication of the type of left-back we are in search of.

Deep Completion passes per 90 vs Progressive runs per 90 with Expected Assists (xA)

The first set of data metrics we want to use is deep completion passes per 90 vs progressive runs per 90 to highlight the players’ ability to affect the final third through ball progression and providing frequent passes within 20 meters of the opponent’s goal.

This also includes xA to give us a complete understanding of the player’s attacking potential.