When Chelsea fans hear the names Oscar and Willian they instantly cast their minds to two moments. Two moments of sheer genius.
They remember the touch, the swivel and the sumptuously curled effort from 25-yards out which beat arguably one of the greatest goalkeepers of all time in Gianluigi Buffon. They remember the moment a breathless contest at Carrow Road was finally sealed after an expertly bended shot from an acute angle nestled into the back of the net.
They are memorable moments players and supporters alike will remember for years to come, not just for the audacity or boldness to take on the shot but the technical excellence to bury it under duress.
Both Willian and Oscar are prodigiously talented and blessed with the famous Brazilian flair and flamboyance which enables them to express themselves and entertain. But what has happened since Jose Mourinho arrived in the summer of 2013 to turn these schemers into sharks?
The general consensus among observers is that Oscar and Willian have become an integral part of Mourinho's team which necessitates hard work and high pressing all across the board.
Defending from the front is nothing new and the two way functionality of attackers to be creative in possession and diligently fulfil defensive duties is a rare trait which Mourinho craves enormously.
They are a rare breed as so few are able to execute what is ultimately a sacrificial role and even fewer are able to make a niche out of it. Juan Mata fell victim to Mourinho's thirst for change in his number 10 as for all the Spaniard's endeavour to adapt and change to become a part of the burgeoning pack of terriers emerging from the Stamford Bridge kennel, he was too lightweight and lacking in bite to fit the bill.
Make no mistake. Mata is no Mario Balotelli, nor is he tactically daft, he can take tactical instructions and plays with an intelligence and awareness that has come to epitomise his football.
However, to be the high octane two-way attacker motoring with boundless energy is all too distinct to the relatively mundane and tedious task of closing down and putting a shift in without the ball.
One of Mourinho's great dogmas is to be organised in all facets - tactically, physically and mentally, to be immaculately prepared for any challenge. That has generally translated to his teams being tight at the back, industrious, adaptable and highly professional.
It has also meant that by virtue of the battling and gritty attitude he instills in his players, chances are created not only through genuine creativity but primarily through causing turnovers high up the pitch to counter attack from dangerous positions.
Some may call it primitive others may praise it, but all in all that is the beauty about football because there isn't one way to play it or even necessarily a correct way to play but rather, there are a myriad of scopes to view and interpret the game to cultivate the philosophies and principles which are to be reflected on the pitch.
At the time and even for some today, the decision to sell the Mata and to do so to a direct rival in Manchester United, however juicy the fee, was almost inexplicable given he had claimed the Chelsea player of the year award two years running and established himself as one of the best players in the Premier League.
However, given the impressive season so far from Chelsea and the fact that Oscar and Willian have well and truly cemented their positions in the team while Mata blows hot and cold, must seemingly be vindication for Mourinho. But at what cost?
Not all as it seems?
While things appear quite rosy at present people tend to forget Oscar cost £20 million and Willian cost a whopping £32 million. These are outlays that are typically reserved for world-class players; Oscar and Willian have hardly proved to be world-class acquisitions, as paltry returns of 27 goals in 130 and five goals in 53 attests to.
Whilst it is absolutely true that they are not in the team to score goals, given how Chelsea did not pay too much more for Eden Hazard it is clear that the Brazilian pair could elevate Chelsea even further if they added more goals to their game.
Their general lack of incisiveness in the final third has belied their reputations as two Brazil's most exciting talents where their industry, energy and tactical discipline has concealed their lack of not only an end product, but the non existence of a dependable source of creativity and guile as two of Chelsea's key attackers.
In terms of their determination, effort and attitude towards diligently carrying out tactical instructions, they are a dream for a manager as they give their utmost week in week out. However, when does the job description begin to take precedence? Whilst the tenacious nature of the pair is quite endearing to supporters and more importantly to Mourinho, Chelsea will have envisioned a greater return on their considerable investments than just graft and effort.
Lack of goals
Chelsea’s lack of a prolific striker last season was well documented and singled out as the sole reason why they failed to win the league title, but on closer inspection it was a lack of firepower in general which proved costly. Eden Hazard was unplayable at times during the last campaign as his game went to another level, but as the Belgian himself admitted after the Champions League semi final defeat to Atletico Madrid that he simply cannot do it all himself.
Hazard’s sensational form ultimately papered over significant cracks in attack which rarely threatened last season and whilst there have been improvements this term, there still remains the sense that Oscar and Willian lack the cutting edge and inspiration that is reserved for them to engineer.
The money aside, their reputations upon arrival were reason enough for great things to be expected and while there have been glimpses especially in the case of Oscar, Chelsea will feel that there is still quite some way to go before the pair justify their price tags.
Arguments to be made
An argument can be made that a more liberal playing style, that is free from the constrictions of Mourinho, would offer a more conducive environment for them to play their natural game and prioritise offensive finesse over defensive responsibility.
On the flip-side it could also be argued that tactical discipline and diligence in tracking back and pressing should be expected not envisaged, which would emphasise the gross one dimensionality of Oscar and Willian. It is open for debate whether the introduction of a more attacking brand of football from Chelsea would bring the best out of the pair however, what is undeniable is the undoubted talents of both.
A prodigious prospect as a youngster, Oscar has forged a reputation since arriving in Europe as a clever and versatile attacker. He is comfortable anywhere along the line behind the striker and given his work-rate and energy would surely be a competent central midfielder.
This appears to be his best position even if he has seldom played in the heart of the pitch for Chelsea and Brazil as his blend of industry and sporadic ingenuity making it a logical fit. He simply does not produce the quality required on a consistent basis to play as a number 10.
Willian on the other hand at his best is a whirlwind of pace, tenacity and bright ideas who at 26, should be at his peak or at least very close to it. As he displayed during his years in Ukraine, he has the capacity to be a devastating player who can dazzle on the dribble, pick a pass and most impressively be unerringly clinical in the box.
However, his game has been considerably subdued throughout his time at Chelsea where his profligacy in front of goal and inability to consistently produce decisive moments in the final third being a major drawback. His moments of quality have been too few and far between to justify a reputation and price tag which harbingers world-class attacking talent.
Throughout what has been a highly impressive campaign, many have praised the abundant strengths of Chelsea and rightly so. Upon his return 18 months ago, Mourinho inherited a strong squad which remained one of the best defences in Europe and in Eden Hazard, Juan Mata, Oscar and Kevin De Bruyne, an array of emerging attacking talent.
Great strengths they may be, but like every squad there were notable weaknesses such as the much documented lack of a predatory striker worthy of succeeding the gaping hole left by Didier Drogba and with Frank Lampard winding down, Chelsea lacked a fulcrum in midfield.
Mourinho's big additions
The choice additions of Diego Costa, Cesc Fabregas and Nemanja Matic have helped Mourinho construct the balanced and dynamic team that he craves which allows him to successfully play in a variety of ways- sit back and preserve a lead, counter or dominate a team.
The latter two requires the presence of a potent striker and the latter in particular requires a midfielder of heightened cerebral qualities who possesses the patience, guile and craft to ensure a sustained and effective exercise of probing in the final third.
Costa and Fabregas's unprecedented success - 17 goals and 15 assists respectively in the league at present suggests that so far, every corner and crevice has not gone unexplored within their game as Matic acts as the glue and intermediary between the rock solid defence and attacking ambition.
It is great for Chelsea's investments to reward them so soon and so handsomely, but it does give rise to more questions. What happens when Costa, Fabregas or Matic are unavailable for an extended period? Who is ready to step up? Are Chelsea's imperious form papering over some rather harsh truths?
There is a school of thought that the moment a team reaches its apex it begins to decline and their demise becomes inevitable. The same could be said about an individual where you would question how it is possible for Costa and Fabregas to maintain such statistical and performance standards?
The pair will go through lean patches and necessitate others to put their hands up to take up the mantle of chief creator and chief scorer. The problem is, when they were dearly needed to step up last season, the likes of Oscar, Willian and Andre Schurrle were nowhere to be seen and look unlikely to deliver the goods if entrusted with the responsibility of leading the team.
The individual quality of Costa, Hazard and Fabregas will ensure they will consistently make an impact - they are genuinely world-class - however, the next tier who granted, are still maturing and growing as players, need to start to justify not only their transfer fees but also their reputations and return the faith shown in them.
This may seem perhaps harsh for Oscar and Willian given the successful integration into the team, but one can only imagine that they are simply horses for courses under Mourinho and would need to adapt and more importantly produce more when they are obliged to express themselves freely and 'play'.
The pairs' international records are steady but again bely their reputation as supposedly gifted attackers. Chelsea missed out on silverware they arguably should have won last season and if players continue to go missing and fail to fulfil their primary roles - defenders defending and keeping clean sheets and midfielders and attackers creating chances and scoring - then the same fate may fall upon the Blues once more.