Under the charismatic Dutchman the change in attitude among the squad has been remarkable
At one stage of last season, the difficulties experienced by Manchester United under David Moyes led to a joke doing the rounds that it was because the headmaster – Sir Alex Ferguson – had been replaced by a supply teacher.
It was a harsh appraisal of Moyes, but results and performances did little to help the Scot confound his critics and United's downward spiral ultimately led to the inevitable dismissal of the former Everton manager.
One inescapable conclusion of the Moyes reign was that the players never really bought into the manager's methods.
He did not challenge them enough, they became restless and, like any unruly classroom led by a supply teacher, the players lost interest and performances deteriorated as a result.
But under Louis van Gaal, the change in attitude among the squad has been remarkable.
If Moyes was a supply teacher, Van Gaal is the university professor accustomed to dealing with the very best and making them even better.
It was a harsh appraisal of Moyes, but results and performances did little to help the Scot confound his critics and United's downward spiral ultimately led to the inevitable dismissal of the former Everton manager.
One inescapable conclusion of the Moyes reign was that the players never really bought into the manager's methods.
He did not challenge them enough, they became restless and, like any unruly classroom led by a supply teacher, the players lost interest and performances deteriorated as a result.
But under Louis van Gaal, the change in attitude among the squad has been remarkable.
If Moyes was a supply teacher, Van Gaal is the university professor accustomed to dealing with the very best and making them even better.
The Dutchman has been at the helm for just over two weeks after missing the start of pre-season due to his run to the World Cup semi-finals with Holland.
But there has been an instant mood change under the new man, both around the team hotel in the United States and on the training pitch.
Players have a spring in their step, but they are also being energised by a healthy element of fear instilled by Van Gaal.
It is as though the former Ajax, Barcelona and Bayern Munich coach has restored the eye of the tiger at United.
Van Gaal's grumbles and gripes about United's tour schedule and his claim that some training session performances have 'not been good enough' give the impression of a man who simply cannot be pleased.
But his demeanour on the training ground counters that view, with the 62-year-old offering vocal encouragement to his players, cheering good passes or goals and sharing jokes with players as far apart on the club's superstar scale as Wayne Rooney and Tyler Blackett.
Senior players have made clear their admiration of Van Gaal's approach and enjoyment of training.
A year ago, during United's week-long stay in Sydney, several players spoke of the intensity and physical demands imposed by Moyes, who believed that the squad's fitness could be improved.
The approach was embraced before the players grew tired of the one-dimensional methods in the early weeks of the season, but the striking difference so far under Van Gaal is the focus on technique, tactics and ball work.
"I train the players in their brains, not their legs," Van Gaal said in Denver. "It is about brainpower."
Drills have included touch and shooting sessions that require the players to receive, control and strike the ball with their weaker foot, while small boxes have focused on slick movement of the ball.
All sessions are monitored closely by Van Gaal, Ryan Giggs and Dutch coaches Marcel Bout and Albert Stuivenberg and the demands for slick technique are incessant.
Some players have struggled to adjust, with the bar being raised high by a manager who places technique ahead of physical fitness.
But the initial response from the players, with impressive victories against LA Galaxy and Roma, suggests Van Gaal's approach has instantly generated the improvement that Moyes was never able to coax from the squad.
The key question now is whether it will continue, but Van Gaal has already won over the dressing room.
Moyes never quite achieved that and it showed with results and individual performances.
He also never instilled the fear factor, but by gaining the respect and fear of his players, Van Gaal is already showing why he is the man United should have appointed a year ago.
