Chelsea's Champions League and FA Cup success last season has seen them endure a progressive transfer window thus far, signing Marko Marin, Eden Hazard and Oscar, 3 players that the former manager Andres Villas-Boas would have been in envy of coaching under his preferent 4-3-3 system - a year too late. These signings have left a consensual impression that Chelsea could be in line for a change in system, from that of what we saw during Roberto Di Matteo's management, where his teams were more set up to counter-attack and react to the opposition. Particularly In the knock out stages of the Champions League, Chelsea had no intention to dominate possession of the ball.

Ostensibly, this was due to the calibre of players Di Matteo had at his disposal, as AVB's number 2 during his reign he had consummate view of his methods and strategies and a better idea of why and how he didn't succeed at Stamford Bridge. Playing a high line when the defenders are not quick enough to keep up with the opposition strikers, trying to deploy youth, when the experienced players still have a lot to offer the team and playing wingers who don't possess the work ethic to operate in physically demanding strategy off the ball. Chelsea just didn't have the quality of personnel spread throughout the team. Di Matteo's man management and utilization of the squad during the second half of the season was the culmination of his reign. Gaining the respect of the 'old guard' whilst giving valuable playing time to what appeared to be squad players under AVB. Di Matteo showed fantastic collaboration and unity in their displays and that's something we didn't see from AVB's side, harmony was key.

Under Di Matteo last season, Chelsea quite frequently set up in what appeared to be a 4-2-3-1 formation, but flattered to deceive changing to a 4-4-1-1 during large spells of high profile games. Generally when teams operate in a 4-2-3-1 they will naturally fluctuate into a 4-4-1-1. In Chelsea's case particularly when off the ball, creating 2 banks of four and defending very deep in compact lines. Their most notable displays against Barcelona and Bayern Munich, bearing in mind that these were two of Europe's most proactive sides (who had the first and second best highest possession and pass-completion stats in any of the five top European leagues) becoming more assertive that reactive football can be successful, but the likeliness of success isn't promising.

Statistically Di Matteo's side had one of the most reactive figures in Champions League football last season, they managed only 44.8% possession overall, averaging 45.7% at home and only 44% away from home. Hardly surprising possession figures considering how compact they were defensively for large spells. Their passing statistics were in correlation too, with Chelsea only providing 3 through balls per game and achieving 375 short passes per game, one of the lowest in the competition. While they committed the most fouls in the competition (184 the 2nd highest) and the worst disciplinary record too, with 20 yellow cards and 1 red. Again, further highlighting how reactive they were and to an extent technically inferior to the opposition.

However, now with Chelsea now possessing some of the finest technical players in Europe, mixed with a strong and experienced spine of Lampard, Terry and Cole (albeit a left-back but a world class one) we can see a different Chelsea side. A more proactive team that can monopolise possession of the ball rather than surrender it, make fluid attacks and cohesive intricate build up play with sudden scintillations of creativity.

Chelsea could very well continue their 4-2-3-1 formation, as the players in the squad are all familiar with it. The new signings Oscar and Hazard could fit into a cohesive and fluid front 4 when attacking, including Juan Mata and Fernando Torres (or a new striker). The most interesting aspect of this new look Chelsea side could be that of whether Mata continues his central role for Chelsea or shifts out wide as an auxiliary inside forward on the right. Juan Mata without doubt, was the technical leader, on-field leader and orchestrator of the side, as he seemed the only technical proficient Chelsea player who could do that last season. However, he was sacrificed to play on the right last season in certain games to make room for a more robust and defensive minded midfielder in Raul Meireles.

Albeit, this season instead of the aforementioned player taking the place of Mata in the centre midfield, Oscar can be that man. The excellent creative attacking midfielder who scored a hat-trick in the U20 World Cup Final, has been playing in the middle of a 4-2-3-1 formation for Brazil senior side this year. At only 20 years of age he has showed plenty of maturity and ingenuity on the ball, traits of classic Brazil number 10. While possessing diminutive pace, vision and great passing, he works very hard off the ball and needs to with a side that possesses the luxuries of Neymar & Hulk as wide forwards. He's an important cog in the team. A central role looks likely for him as he doesn't have wide play characteristics either.

Hazard and Marin are two similar players, very rapid, tricky and direct. They may often lose the ball with their ambitious styles of play, at times they will succeed at it, other times they will fail. However, it is imperative that in the middle of a 4-2-3-1 system behind the striker the midfielder is clever in possession, picking his moments to play the decisive ball, setting the tone of the side and forming what the Brazil coach Paulo Autori once called 'small societies' during play. Top European sides such as Madrid and Barca have a trio of players who form mutual understanding on the pitch that can open up a team, regardless of their defensive reasoning. If you look closely at Barcelona's games you will see that Alves-Xavi-Messi enjoy possession of the ball in close proximity to each other along the right hand side. Just like Marcelo-Alonso-Ronaldo do for Madrid, and recently I have seen Oscar perform this act of 'small societies' with Marcelo and Neymar. With Marcelo's forays forward, allowing Neymar to cut infield and link up with Oscar.

Perhaps we could see Chelsea do the same with Ashley Cole bombing forward and allowing Hazard to cut inside and link with Oscar?

This is the Chelsea side I think we are likely to see with Oscar in the middle of the 3 behind the striker, Mata as an auxiliary right winger and Hazard on the left wing. Mata and Hazard have the natural tendency to cut inside as a ball-playing wide midfielders that drift inside into central playmaking positions. In tough circumstances, the 3 attacking players behind the striker, these players possess the dexterity and nimbleness to elude even the most shrewd markers. This type of player has never been so popular. Today we don't often see a winger in the fashion of Antonio Valencia, who will look to beat his man and get down the touchline to produce a cross. This is evident of how the game is continually changing.

One would believe that given their inclination to cut inside in-between the lines would cause congestion with neither Hazard nor Mata stretching the play and keeping the width. Spain were castigated for their approach and style of play, playing two ball-playing wide midfielder's cutting inside where Xavi was positioned made their football look very horizontal and predictable. This could lead to Mata being played on the left wing and Hazard on the opposite wing, providing width and direction, but nullifying the creative ability of the aforementioned. Another option would be to give Mata the licence to cut inside and Hazard to use his pace to stretch the play and stay on the periphery. Either way this adds tactical flexibility to Chelsea allowing them to alter their shape and style during games.

Ramires or Lampard covering ground and making runs off the ball can provide a disturbance towards the opposition and a more direct threat if Chelsea can't break down a reactive team defending very deep with 2 banks of four. Both players are very similar in how they score their goals, frequently making late runs into the box for pull backs or tap ins, especially in crucial moments. When one goes, the other can sit and cover, . This is the joy of the double pivot, two players don't necessarily have to sit, unless the team are playing two highly attacking full-backs, which Chelsea only have two moderate attacking full-backs in Ivanovic and Cole, although mainly the latter. In what is now the autumn of Lampard's career, we witnessed him play a more tempered and responsible role, using his brain and raw stamina produce colossal performances in midfield for Chelsea in the latter stages of the Champions League especially. Whether we continue to see him play in the base of the midfield and offer himself for passes behind opposition midfielder's.

Premier League champions Manchester City set the bar high last season, although they didn't achieve what many thought would be an appearance in the knock out stages of the Champions League at least. However, their dominance against sides in the league week after week was evidence of their quality, out shining their neighbours Man United, their best performance arguably the 6-1 win at Old Trafford. Showing often last season that the game is far developing into a team of midfielder's rather than traditional wingers/strikers. Small, diminutive, technically proficient players instead of the tall, powerful and direct players have become a popular consensus. Chelsea appear to be doing the same, but what will be interesting to see is how Di Matteo can tactically adapt to the players he'll have at his disposal. It would be a complete opposite to the sides he put out against quality superior opposition.

Below I will convey some line ups that Di Matteo opted with in high profile games:

In the 2-1 defeat away to Man City last season, Chelsea set up in what initially seemed as a 4-3-3 but became a 4-5-1 when defending, they played a narrow midfield 3 of Meireles Mikel and Lampard. All in close proximity to each other. Surrendering possession, thus allowing Man City to pin back Chelsea in the attacking third with an aim to hit them on the counter attack with Ramires' pace and Mata distribution of the ball. This was a common theme in Champions League games against Barcelona and Benfica (see below).

This is the line up Di Matteo chose to play against Barcelona, with the same aim to hit Barcelona on the counter-attack which they done with Ramires as the outlet. Providing the assist for Drogba to win the game 1-0. The same procedure followed in the 2nd leg at the Nou Camp, Ramires once at the heart of it, playing a one-two with Frank Lampard before being put through on goal and scoring a delightful chip.

In the Champions League 1/4 Final we saw Chelsea field the same formation, but with Ramires in the middle to replace an injured/rested Frank Lampard and Kalou on the wing. However, Ramires still found himself with space down the right to attack with a good run, releasing the ball to Torres for him to set up Kalou with the goal.

Do you see the theme? Even against Liverpool in the FA Cup Final. Di Matteo went with a 4-3-3 (4-5-1 when defending), hit Liverpool on the counter attack with Ramires again the goal scorer, Mata the provider.

Di Matteo now has an inflation of attacking players, and with Roman Abramovich keen to continue Chelsea's European success with a more youthful squad, and different style of play to what we saw last season. RDM will have to show how he cam implement new ideas and methods for a Chelsea squad that contains players such as Oscar, Hazard, Marin, Sturridge, Torres, and Ramires. Chelsea enter a new era, but still contain some of the 'old guard'  that could prove to be vital through this phase of transition. Every club during at some period will go through a transitional phase and this season will be Chelsea's. Success may not come as quick as fans or the owner may want, but patience is paramount. Just how much patience Abramovich has, we will have to see.