As Sir Alex Ferguson celebrates 25 years at Manchester United, TEAMtalk guest Adam Bate puts the manager's longevity down to his adaptability.

For many the personification of genius is the wizened portrait of Albert Einstein in old age. And yet, the famous professor was in his early forties when he received the Nobel Prize for Physics in 1921. Moreover, his key research on the subject had been done while still in his twenties.

Likewise, the iconic image of the football manager remains the grey-haired suited figure on the touchline - a man who has seen and done it all. In other words, it is of a man who looks very much like Sir Alex Ferguson.

Again, the reality is somewhat different. Indeed, 17 of the last 20 coaches to lift the European Cup were under the age of 50 when they first did so. Even football management, it would seem, is a young man's game. And Ferguson - the old maestro - is somehow continuing to buck the trend.

Today, two of the game's most celebrated figures are perceived to epitomise the new appearance of the football coach. Jose Mourinho came to exemplify youth itself with his exuberant antics during Porto's journey to the Champions League title in 2004. Pep Guardiola went even further - becoming the youngest man to coach a side to Champions League glory in 2009 at the age of just 38.

But these men are hardly exceptions to the rule. The Dutch trio of Guus Hiddink, Johan Cruyff and Frank Rijkaard were all in their forties when they lifted Europe's greatest prize. So were the Italian trio of Arrigo Sacchi, Fabio Capello and Carlo Ancelotti.

Even those coaches that we may now perceive to be old did in fact enjoyed success at a surprisingly young age. Vicente Del Bosque's walrus-like moustache belied the fact that he was a mere 49 years old when Real Madrid became Champions of Europe back in 2000. The grand old man of football himself, Giovanni Trapattoni, claimed his solitary European Cup win at the age of 46.

Of the last 20 men to win the trophy, only Raymond Goethals was older than Ferguson. So how does the old fella do it? Well, for a man who is notoriously stubborn it is perhaps ironic that one of his greatest strengths has been his adaptability. The contrast with many of his peers is stark.

While Sacchi's Milan - with their pressing game - provided arguably the last great tactical innovation the game has yet seen, the Italian was finished as a top level coach at an age when Ferguson was winning the treble. Once his vision was realised and subsequently adopted elsewhere, Sacchi failed to stay ahead of the curve.

Giovanni Trapattoni's footballing education occurred in the years of Catenaccio and his ultra-defensive approach with Ireland can now feel like something from a different era. His protégé Fabio Capello, meanwhile, has struggled to adapt to the peculiar demands of international management so late in his career.

Relatively speaking, Ferguson's flexibility has been astonishing. His tactical view of the game has continually evolved. After accepting the vulnerability of his side away from home in Europe, he made United tougher to beat and experimented with the 4-5-1.

With Wayne Rooney, Carlos Tevez and Cristiano Ronaldo in tandem, Ferguson then dabbled with a strikerless formation and - just when some were thinking it was dead - he has since reintroduced the 4-4-2 at Old Trafford.

When it comes to player power Ferguson has also moved with the times. Some thought there would be no way back for Rooney at Manchester United after his extraordinary transfer request, but Ferguson seemed to accept this was all part of the modern game and managed to keep his star man.

All the signs are that we can expect to see younger coaches at the top level of the game in the years to come, with Andre Villas-Boas and Thomas Tuchel leading the way. But don't be surprised if Sir Alex Ferguson keeps on adapting to the ever-changing challenges that football provides - and continues to buck the trend.

Follow Adam on Twitter at @ghostgoal and check out his blog at GhostGoal..