Chelsea went on one of the best premier league runs ever, winning 30 of their possible 38 games in the 2016/17 Premier League season. However, Chelsea’s start to the season followed a completely different trend to the rest of their season; while the team won 3 out of their 3 games, the first was an unconvincing 2-1 win against West Ham (who finished the season with 45 from 114 available points), followed by a 1-2 win against Watford (who finished 17th in the table), both games in which Costa had to score an 87+ minute goal to save the tie, and a routine 3-0 win over Burnley. The team seemed to be struggling, regardless of the immense talents of Hazard, Costa and their 35 million pound star signing N’Golo Kante at their disposal. Signs of a collapse were imminent as in the next three games the team drew 2-2 against a Swansea side that would go on to be relegation candidates, and then two humiliating losses against rivals Liverpool and Arsenal 1-2 and 3-0 respectively. Yet, since the defeat to Arsenal, Chelsea went on to win their next 13 games in a row, 1 win away from the Premier League record for most consecutive wins in a season, scoring 32 goals and conceding only 6 and defeating title contenders Manchester City, Manchester United and Tottenham Hotspurs along the way. From that point on they would only go on to lose 3 more matches and draw 2, leaving them with a close to record breaking 93 points out of the available 114 for the season. So how did Chelsea change their season around in practically a week after the defeat to Arsenal at the Emirates? The answer is simple: Antonio Conte. But more specifically, the change in formation that Conte decided to use.

Antonio Conte inherited the squad from Jose Mourinho, who had set up the team to play in a defensive style 4-2-3-1 formation. Conte however, had traditionally played a 3 at the back formation during his time at Juventus and the Italian national team. Nonetheless, given that his players already knew the system, he decided to play the same system, changing certain aspects to suit his creative and defensively sound values as a manager. The 4-2-3-1 formation therefore, was what he used against West Ham on his premier league debut in the 2016/17 season as Chelsea’s manager. He continued to use this up until and including the Arsenal game. After that game, Conte decided to scrap the system that had been left to him and decided to implement his own formation given the players he had; he decided that the 3-4-3 formation would be the best formation in order to not only guarantee results, but to finally get his players playing the style that he wished to implement, one of attacking fluidity and interchangeability between attackers as well as a commanding, dominating and organised defensive unit. But why did the 3-4-3 formation work so much better than the 4-2-3-1 formation? One of the best ways to answer this question is to examine the team’s statistics in either formation. To do this, I will examine the difference between the formations against two opponents in both the home and away fixtures, namely Liverpool and Arsenal (the reasoning for this is that Chelsea lost to both these teams while using the 4-2-3-1 formation and either drew or won in the second game against these teams in the second half of the season with the 3-4-3 formation).

Firstly, let us analyse the two encounters with Liverpool, in which Liverpool used a 4-3-3 system on both occasions with only 2 changes in personnel. In the first encounter in the first half of the season when Chelsea were using the 4-2-3-1 system, Chelsea had 52.7% possession while Liverpool had 47.3% possession. In the second encounter of the season when Chelsea were using the 3-4-3 system and drew 1-1 with Liverpool, Chelsea had a much decreased 37.6% possession while Liverpool had 62.4% possession. While this data might initially seem extremely surprising since one usually associates domination of possession with success, we can infer that the switch in style and formation of play for Chelsea led to less time on the ball with a greater emphasis on defensive solidity and making sure that the opponent was restricted in the chances they created, even though they were holding on to the ball for more time in the match than this Chelsea side.

This is clearly evident as in the first encounter, with 47.3% possession Liverpool were able to take 13 shots (5 on target) while in the second game, with 62.4% possession Liverpool were able to take 7 shots (3 on target), a dramatic decrease in the conversion of possession to chances. Chelsea, meanwhile, took 14 shots (4 on target) with 52.7% and 8 shots (2 on target) with 37.2%. We can see that the conversion of possession to chances for Chelsea actually increased, telling us that they were playing more of a counter attacking style of play where the team would defend for extended periods of time and draw the opponent in and then was able to counter and depend on the pace and skill of Hazard, Costa and Pedro to score goals. Therefore, the 3-4-3 system and style worked far better than the 4-2-3-1 formation where the team changed to being defensively oriented with an emphasis on counter attacking; Conte made the other team’s possession less useful and his own team’s possession far more productive. Essentially the same exact story is told about the Arsenal encounters; In the first encounter in the first half of the season when Chelsea were using the 4-2-3-1 system, Chelsea had 50.5% possession while Arsenal had 49.5% possession. In the second encounter of the season when Chelsea were using the 3-4-3 system and won 3-1 against Arsenal, Chelsea had a much decreased 41.7% possession while Liverpool had 58.3% possession. However, Chelsea had increased their shot taking from 9 (2 on target) to 13 (6 on target) while Arsenal had a decreased shot taking stat from 14(5 on target) to 9(5 on target). This again shows that the change to the 3-4-3 system made Chelsea’s possessions less frequent but more meaningful, coupled with increased possession to chances conversion rates, whereas it hampered their opponents, increasing their possession on the ball but decreasing their effectiveness and ability to defend against Chelsea’s lightning quick counter attack.

While it is evident that Chelsea were able to play a certain successful style of game with a switch to the 3-4-3 against the so called ‘big’ clubs in premier league football, against the smaller teams such as Burnley - teams that Chelsea are expected to win against - the formation change seemed to work opposite to how it does against the top clubs. While against Arsenal and Liverpool Chelsea had less possession with the 3-4-3 system when compared to the 4-2-3-1 system in each leg of the season, against the smaller teams Chelsea had increased possession. For example, against Burnley, in the first encounter of the season which ended in a 3-0 win with the 4-2-3-1 formation, Chelsea restricted Burnley to 39.1% possession, In the second leg of the season in the 3-4-3 formation however, Burnley were held to 28.3% possession. Again, contrary to the output against the top teams, Chelsea had a decreased number of shots per possession statistic against smaller clubs. In the first leg Chelsea had 22 shots and 10 on target, which decreased to 13 shots and 2 on target in the second leg. So Chelsea had more possession for less chances created against the smaller club. From watching Chelsea play against both types of teams, it is evident that the team preferred to defend tightly against top teams and play on the counter attack, while playing smaller teams the game plan was to out-possess the opponent as Chelsea had far better quality of players than the other teams and were able to do so. Therefore, we can see that Conte used the 3-4-3 effectively against both top and bottom teams in the premier league.

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