When José Mourinho took the helm at Chelsea in 2004, he completely changed the landscape of the Premier League, transforming the dominance of Arsenal and Man Utd into the Chelsea era. He was appointed manager after a fantastic career at Porto, winning every domestic and European title worth mentioning. That career continued after Chelsea - winning the Champions League with Inter, and making Barcelona look mediocre in La Liga with Real Madrid.

So when André Villas-Boas went on a similar career path with Porto, finishing his first year undefeated in the league and claiming both domestic and European cups, the comparisons with Mourinho were unavoidable. Indeed, the two have been working together for years, as Villas-Boas was head of Mourinho's 'Opponent Observation Department' at Porto, Chelsea and Inter before moving on to become manager of Portuguese club Academica.

But the only comparison to be made between these Portuguese gentlemen is their career path from Porto to Chelsea. Villas-Boas and Mourinho have very different strategies and theories on how football should be played - Mourinho using adaptive tactics where Villas-Boas prefers familiar shape, Mourinho using mind-games where Villas-Boas prefers math, and so on.

Villas-Boas and the Chelsea connection

It's amazing to think that one of the richest and most successful Premier League clubs in the last 10 years sacked Carlo Ancelotti (who won the Premier League and FA Cup in his debut season, scoring more than 100 goals in the league) to bring Villas-Boas to the club - a person who got his first job as manager only a couple of seasons ago. There is no doubt he came highly recommended by Mourinho's camp - a camp that is still respected in west London despite the bad blood surrounding Mourinho's departure.

Was it the right move, did the marriage make sense? In theory it was a great idea; bring in young blood - someone who can modernise the club, someone who is easier to control than Mourinho, someone who has fresh ideas on how to play football. But in praxis, Villas-Boas came with pioneering ideas into a team where the old-school conservative players still reign the dressing room.

The 'Mourinho Core' of John Terry, Didier Drogba, Frank Lampard and Ashley Cole had an average age of 32 when Villas-Boas joined Chelsea, a hard age group if you want to teach footballers some new tricks. With meticulous training schedules, intricate tactical instructions and radical theories in areas like pressing (where the basics are taught at a very young age), Villas-Boas had little chance of persuading the old boys to re-think their approach.

Villas-Boas is probably convinced that his approach would have worked, if the players had done exactly what he told them to do. And he's probably right - his mathematic and detailed approach to tactics is probably the next phase in the future of football, especially as more intuition-driven managers like Alex Ferguson and Harry Redknapp are starting to reach an age of retirement. But will players over 30 be prepared enough to adapt now, when they might have to find other clubs only a few years later - clubs who will have traditional setups and training routines?

The Villas-Boas Method - Training

So how is Villas-Boas pioneering football? Apart from being the first truly attack-minded manager at Chelsea since Roman Abramovich took over, his training methods are thoroughly structured and researched, focusing more on situational moves instead of proven methods of technical repetition.

For example; one of his defensive training methods is to have two sets of back fours, starting from behind the goal and running up towards an alternating attack line of four and five players at a time.

Backline A runs up and tries to defend against Frontline A, and when the attack has been dealt with (either by a goal or a clearance out of the training zone), Backline B runs up towards Frontline B, while Backline A runs back behind the goal-line.

By starting at the same distance from the edge of the penalty area, defenders learn how to move into position from an awkward zone, and how to deal with overwhelming attacks of four or more attacking opposition players.

This sort of strict situational approach to training is relatively new at Chelsea, although Mourinho had similar routines in terms of dividing the pitch up into zones and prioritising them according to what tactics he wants to apply.

Villas-Boas prefers wide play, and so he focuses a lot of the training in the central zones. That might sound contradictory, but training the central zone is actually training for distribution out wide. The above example is just one of many, and was taken from Villas-Boas' pre-season notes and open training sessions. The situation-based training is interesting, as it assumes that certain scenarios will occur during a match, and it also takes away time for training in more general areas.

The Villas-Boas Method - Tactics

In a lot of Villas-Boas' leaked notes there are references to wide play and how the central striker is vital in how the wide players operate. The striker's main role is to provide opportunities for the wide players to serve through balls into the box, or to draw defenders out of position to allow more space for wide players to get into crossing positions.

The Portuguese manager preferred a 4-3-3 shape at Porto, very similar to the skewed midfield shape employed by Arsene Wenger at the start of this season - Fernando as the anchor behind Moutinho and Guarin. The skewed midfield trio pivots and rotates to push one or two player up the pitch at any given time, depending on opposition movement. It's also worth noting that Villas-Boas has a very strict tactic in mind, rarely altering positions to accomodate certain player types.

At Chelsea he used the same strategy, with plenty of options for the midfield trio. Michael Essien, John Obi Mikel, Raul Meireles, Ramires, and Oriol Romeu are all versatile midfielders, and fit perfectly into a pivoting triangle, at least in theory. But the 'old guard' at Chelsea saw it as sacrilege to overlook Frank Lampard, who works better in a no 10 role higher up the pitch, and enjoys freedom to roam.

Villas-Boas had no real option than to play Lampard as often as possible, a player who de-constructed Villas-Boas' intentions in midfield. If the Portuguese manager had the choice to pick any player he wanted without expectations on selection from fans, dressing room and board room, he would probably have picked Ramires, Meireles and possibly even Romeu in front of Essien or Mikel.

Pressing and Marking
There are a lot of similarities between Pep Guardiola and Villas-Boas in terms of pressing approach - both prefer to press from the front and quickly gain back possession when it's lost. The problem is that Guardiola implemented that kind of pressing in a highly energetic team just in the midst of their career peaks, while Villas-Boas needed a 33-year old Didier Drogba to press centre-backs for 90 minutes.

The failure to implement adaptive tactics depending on player personnel and opposition movement was probably his biggest flaw, and it's a flaw he shares with Arsene Wenger. Guardiola gets away with it because he has a group of players who can alter the outcome of a game on their own, but when you have an ageing squad full of stubborn characters, you need to adapt your tactics to get the best of what you have available.

But...this is an Arsenal site?

There is a very good reason for talking about Villas-Boas, and that's the fact that Arsenal will sooner or later be in the same position as Chelsea; looking for a new manager. Villas-Boas is exactly the type of manager you'd expect the board to consider - a young and fresh option in the same vein as Jurgen Klopp, Massimiliano Allegri or Pep Guardiola. After all, pioneering methods and modernity has been part of the club since Herbert Chapman implemented the WM formation in the 20's.

Our current squad is full of players that are young enough to adapt a new way of thinking, but the question is if we'll have an 'old guard' of Szczesny, Koscielny, Wilshere and Walcott whenever Wenger retires, and will they be able to adapt to new ways of playing football? Villas-Boas is the perfect example of what happens when you try to put a contemporary mind in charge of conservative heads.

However, it's also worth noting that Arsenal went through a similar phase 16 years ago, appointing a truly unorthodox French manager who reshaped the club from top to bottom, and doing it with a highly conservative "old" guard of Winterburn, Adams, Keown, Dixon, Seaman and Parlour. Eventually, these players accepted the changes and ushered Arsenal into a new era of success.

With Villas-Boas being sacked before the season ended, Abramovich clearly ran out of patience and succumbed to player power. The Portuguese manager could have made quite the difference if given a proper chance, but now Chelsea have to look for yet another manager.

Chelsea's demand of trophies + style is similar to that of Real Madrid's, but not even Mourinho's current free-scoring Real Madrid are considered stylish enough for the Madrid directors, even though they've scored 85 goals in their last 25 league games, averaging 3.4 goals per game (!!!). And if that's not considered stylish, how the hell was Villas-Boas supposed to bring style to Stamford Bridge in less than a year, all while expected to reshape the club into something modern?

Abramovich wants instant success, instant transformation and instant style. It's not going to happen, and that should be a reminder for those Arsenal supporters who are complaining about the current lack of trophies - success is a long-term plan. Chelsea are the prime example of what happens when you attempt short-term success.