12 years ago, Arsene Wenger had just won the 2003/04 league title and was basking in the glory of going a whole season unbeaten. This looked to be a watershed moment for the Gunners as they seemed set to go on to dominate the game in this country for years to come, as well as having eyes on finally winning the biggest of them all - the Champions League.

As it turned out, of course, no such dominance ensued. The 2004/05 campaign saw some upstart called Jose Mourinho breeze in, heralding himself as 'The Special One' and then duly winning back-to-back league titles with Chelsea, leaving Wenger with his nose firmly put out of place.

What was meant to be the Frenchman's dynasty, following Ferguson's in the '90s and Paisley and Fagan's in the '80s, became a nightmare as the Gunners fell from their perch.

12 years on, Arsenal are still yet to win another title, despite a few near misses, and the second half of the Wenger era isn't looked back on as a qualified success at all when arguably it should have been better than the first.

Why has this happened? Well, many feel Wenger was caught up on and then usurped in terms of managerial techniques. In the late '90s through to the turn of the century, the Frenchman was seen as a pioneer. The way he got his teams to play football combined with the new approach to things like diet, training and psychology off of the pitch caught everyone napping.

Naturally, going unbeaten through a season is going to make your rivals seriously look at what you're doing right. Sports science and that whole area of the game began to boom and Arsenal's rivals soon caught up and then overtook, because whilst they took on this new-fangled idea and evolved it, Wenger seemed to stand still and he's been playing catch up himself ever since - it can't be sheer coincidence that the Gunners have some of the most injury plagued players around.

Evolution, frequently instead of revolution, is the key in football. Liverpool's famed success came through a line that stretched from Bill Shankly to Kenny Dalglish and Manchester United had one man to do the same, Sir Alex Ferguson. The constant ability to keep pace with your rivals and the modern trends around the game as well as constantly churning out winning sides is what makes the good great and Wenger has gone from the leading man to one of the chasing pack in the last decade.

So, where does his great rival Jose Mourinho come into this? Well, first thing's first, it's way too soon to call the run of three lost games - prior to the Northampton Town win in the EFL Cup - a crisis. The fact it's caused so much hoo-hah is because it's Mourinho and it's Manchester United. Claims they're not going to finish in the top four because of this and that they're a long way from achieving anything are far too premature but, there is a case for suggesting the former Chelsea man isn't going to achieve the success of his early career - the success the Man United fans expect.

Since 2010 Mourinho has two league titles to his name, for nearly anyone else that's a decent return, but for Jose, that's a bit of a drought and it could just be because he, like Wenger, is standing still. Wherever the Portuguese tactician has gone he's had pretty much the same coaching staff, the same ideas have gone onto the training field and the same type of players have been bought. He's never really done something where you've thought 'wow this is different for a Mourinho team'.

Now, whilst having a clear idea in mind as to how you want to play has its merits, not even entertaining the idea of tweaking things seems uncharacteristically careless for a planner as meticulous as the former Chelsea boss.

When he joined the Blues he enjoyed great success as he helped develop the now well over-used 'Makelele role' as well as aiding 4-3-3's rise to the top of the list in this country. He enjoyed that head-start Wenger did when he came in in 1996 and teams started to try and emulate the Blues instead of Arsenal. 4-3-3 became the formation, the 'Makelele role' was afforded to anyone that could play as a holding player and Mourinho was leading the charge, but as things have gone on over the years, the charge has caught up with him - sound familiar?

Since Mourinho's initial glut of trophies, tactics have certainly moved on. We've seen 4-2-3-1 become the vogue in the Premier League whilst the 3-5-2 has enjoyed a resurgence. Pressing and counter-pressing are buzzwords and the likes of Pep Guardiola and Jurgen Klopp have come onto the scene with completely new ways of playing the game - they are now the pioneers and how they evolve over the years remains to be seen - Guardiola at least has shown clear signs he knows how to.

But what of Mourinho? The man who for some time looked unstoppable has been found out in the last half a decade and whilst his methods still work to some extent, it's no longer the extent to which Man United are going to win the league on numerous occasions. He wants to emulate Sir Alex Ferguson at Old Trafford so he'd better start doing it properly. Ferguson changed his coaching staff and players around regardless of reputation or previous success when he saw fit and always kept up with the latest tactical innovations, and whilst we may never see the likes of him again, Mourinho would do well to take some of that advice going forward.

If he doesn't, he could be the one called a specialist in failure ten years from now.