For the second time in the Premier League this season, Chelsea lacked their usual attacking fluidity against Swansea at the weekend. The other occasion in which they really failed to create much was in their goalless draw at Loftus Road against QPR, with the common feature of both games being the absence of Juan Mata.

With the summer arrivals of Eden Hazard from Lille and the Brazilian wonderkid Oscar, there was much buzz around Stamford Bridge before a ball had even been kicked. And while both have showed signs of their undoubted talents, it has been the little Spaniard that has become the star of the show.

It’s remarkable to think that Mata was recently left out of the Spanish international squad, yet he seems to have an outstanding temperament and has reacted in the best possible way, producing an even better string of performances. Mata has outshone both his new colleagues and his contemporaries in the league, arguably being the player of the season to date.

Just as they did against QPR, Chelsea lacked their usual cohesion and fluidity which has caused opposition defences so much trouble. Although the attacking three which play behind Fernando Torres have designated defensive positions – Hazard left, Oscar central and Mata right – the key feature of their attacking play has been the constant rotation.

Mata is vital to this flexibility as he is the least naturally suited to his starting position of the three. Hazard is comfortable running at a full-back on the left and Oscar is most naturally suited to the central area in which he starts, however Mata does not want to be restricted to the right hand side. His tendency to float across the pitch encourages the other two to do so, in order to find the space they desire.

The difference in the style and effectiveness of Chelsea’s three attacking midfielders against Swansea to their previous away fixture with Tottenham, during which Mata was superb, highlights this. Whereas Mata influenced the game between Hazard and Oscar, his replacement Victor Moses preferred to stay wider in areas which suit his game better.

Moses is obviously a very different player to Mata and as such brings different qualities to the team. The purpose of this analysis therefore is not to criticise Moses, since he brings a different dynamic to the team, which will be required at times. He was excellent in the Capital One Cup victory over Manchester United and tormented Alexander Buttner throughout the game with his direct running.

Given their resources, the lack of attacking options beyond Roberto Di Matteo’s preferred starting eleven is a little concerning. Moses will provides his manager with his best alternative, certainly more so than the erratic Daniel Sturridge. He will undoubtedly have an important to play in Chelsea’s season and a comparison to Mata seems harsh, but serves the purpose of highlighting his importance rather than Moses’ shortcomings.

The comparison between the player influence charts of Moses against Swansea and Mata against Spurs is revealing in showcasing what Chelsea lacked at the Liberty Stadium. Not only does Mata involve himself more in general play but his superior passing ability allows him to look forwards and open up defences. Whereas Moses tends to play more simple passes inside or backwards, since this is not his strength, Mata plays a vast number of balls directly forwards, into and around the penalty area. It goes without saying that this vastly increases the team’s ability to create goal scoring opportunites.

The knock on effect of Mata’s absence on Oscar and Eden Hazard is also interesting. Devoid of his insistence on playing all across the line, the pair were far less fluid themselves. To take Oscar as an example, against Spurs he received a lot of his passes on the right hand side since Mata had departed the area and created space, whereas against Swansea he received the majority of his passes in the central third of the pitch.

Aside from anything else, this all made their attacking play considerably more predictable and easier to defend against, even for a Swansea side who have really struggled at the back this season. Considering that they have reverted from a team focused on power to one which relies on intricate play, the lack of movement seriously hampered Chelsea.

With a vital and tricky Champions League tie coming up against Shakhtar, Di Matteo will be desperately hoping that his new talisman has fully recovered from the groin strain which kept him out at the weekend. His importance is ever growing and he will be needed on Wednesday night.