Ruthless Erik ten Hag is proving he's a Man Utd manager in Sir Alex Ferguson's mould after brutally axing Harry Maguire as captain and kicking David de Gea out

Long-term squad planning was the key to Ferguson's sustained success in his trophy-laden, 26-year reign at Old Trafford, and he was never afraid of showing players the door, no matter how much they had given the club.

Ferguson gave an insight into how he managed a player's decline during his collaboration with the Harvard Business School. In a publication titled Ferguson’s Formula,the Scot outlined eight aspects of his leadership of United, one of which he called ‘Dare to Rebuild Your Team’.

"The goal was to evolve gradually, moving older players out and younger players in,” Ferguson explained. "Some players can go on for a long time, like Ryan Giggs, Paul Scholes, and Rio Ferdinand, but age matters.

"The hardest thing is to let go of a player who has been a great guy — but all the evidence is on the field. If you see the change, the deterioration, you have to ask yourself what things are going to be like two years ahead."

Ferguson was an expert at spotting when a player was on a downward curve and, despite him describing it as “the hardest thing”, he often delivered the message in a cold-hearted way.

Take his treatment of Ruud van Nistelrooy, who had scored 150 goals in five seasons. Speaking to Gary Neville on The Overlap, the Dutchman recently described how Ferguson told him his days at United were numbered hours before the final game of the 2005-06 season against Charlton Athletic, leaving him out of the matchday squad and barring him from attending the game. His methods were out of the Tony Soprano playbook.

Van Nistelrooy recalled: "It was in the hotel, he got me travelling to the hotel for a home game. I remember just waking up in the morning and going towards the game and he decided overnight and said, 'You're not in the squad. You'll be brought to Old Trafford and get your car and that's it'. That was the end.

"I started pre-season but you knew he was moving on without me and putting the future of the club into other players, so that was clear."

Ferguson was also ruthless with Roy Keane, sacking the Irishman in the middle of the 2005-06 season after his infamous, fiercely critical appearance on MUTV following the 4-1 thrashing by Middlesbrough. Keane admitted that after being told the news, he sat alone in his car and burst out crying.

Two years earlier, the manager broke David Beckham’s heart when he told the much-loved winger he was going to be sold to Real Madrid. Beckham recently admitted he could not bring himself to watch United on television for three years after he left the club for Santiago Bernabeu in 2003.

Not even United’s inspirational captain Keane or a global icon like Beckham were beyond reproach from Ferguson, who sensed that both players had lost sight of who was in charge.

"I think Roy realised he was coming to the end of his playing career and was starting to think he was the manager. He was assuming managerial responsibilities, and, of course, it’s not a managerial responsibility to go on Manchester United television and slaughter your team-mates," Ferguson wrote in his 2013 autobiography.

"The one thing I could never allow was loss of control, because control was my only saviour. As with David Beckham, I knew the minute a football player started trying to run the club, we would all be finished."

Ten Hag is yet to kick a boot at any of his players or, to anyone’s knowledge, make them cry. But he has made tough calls on four players who all had big status for different reasons. First he took action against Cristiano Ronaldo, one of the greatest players in the world, a United legend and a man who doesn't take criticism well.

The manager gave Ronaldo only a handful of appearances after the player had missed pre-season, and when the Portugal forward refused to come on as a substitute against Tottenham in October and left Old Trafford before the full-time whistle, Ten Hag excluded him from first-team training for a few days and he was dropped for the next match against Chelsea.

To tell the truth, Ten Hag could have been tougher on Ronaldo, and he strangely brought him straight back into the team only a week later, starting him in four consecutive matches leading up to the player’s infamous interview with Piers Morgan. He also did not punish Ronaldo at the start of the campaign when the Portuguese left a pre-season friendly with Rayo Vallecano early.

In the end, Ronaldo made Ten Hag’s decision for him by rescinding his contract with the club during the World Cup. But he was not willing to dwell on the saga, and in his first media appearance after Ronaldo’s departure, the manager drew a line under it.

"He's gone and it's the past," Ten Hag said. "We are now looking forward and we're looking to the future."

Ten Hag also seemed willing to compromise on another high-profile player in De Gea. The Dutchman encouraged the goalkeeper to play out from the back in pre-season and in the first two matches of the campaign, but after the 4-0 horror show at Brentford, the Spaniard mostly abandoned his attempts to play short passes to his team-mates, often going long instead.

Ten Hag defended De Gea from criticism even after his high-profile mistakes against Sevilla and West Ham later in the campaign, and said he wished for the goalkeeper to renew his contract. But De Gea’s performance in the FA Cup final seemed to turn Ten Hag’s head and United later withdrew their offer of a new contract to the Spaniard, leading to them moving to sign Andre Onana, the manager’s No.1 at Ajax.

De Gea was United’s longest-serving player and had acted like a captain in recent years, often coming forward to talk to the media after the team’s most traumatic defeats. But Ten Hag could see that his limitations with the ball were only going to hold the team back, and that he was no longer the miracle shot-stopper of old either.

The contract withdrawal certainly made United look clumsy and indecisive as well as ungrateful for De Gea's 12 years of service, but it was undoubtedly the best thing for the team's future. United needed to move the Spaniard on to fully realise Ten Hag's vision for his side, and in Onana they have signed perhaps the best ball-playing goalkeeper in the world.

Ten Hag's latest demonstration of his authority was telling Harry Maguire he would no longer be the club's captain. As with De Gea, the manager never criticised his centre-back in public, and always defended him to the media despite rarely picking him in the matches that mattered (Maguire made only eight Premier League starts last season).

The Dutchman could easily have left things as they were and kept Maguire as the official captain with Bruno Fernandes as the de facto skipper, as was the case for most of last season. However, continuing with the status quo would have meant giving Maguire a role that did not reflect his real standing in the squad and would have been unfair on Fernandes too. The decision may have angered Maguire, but it was also the reality check the defender needed.

It also might motivate Maguire to look for a new club, which would give United a much-needed cash injection to fund future transfers.

Ten Hag does not just take action against players who he thinks no longer have a future at the club. For example, he dropped Marcus Rashford from the starting line-up for the fixture at Wolves when the striker was in his best moment of form after he had overslept and been late for a team meeting.

"Internal discipline" was how Ten Hag justified that call before the real reason was known, but the manager also showed he did not hold grudges and brought Rashford on at half-time at Molineux when the game was goalless. Rashford inevitably struck the winner and Ten Hag embraced him at full-time, demonstrating that all was forgiven.

Seven months later and Rashford has just signed a long-term contract, making him United's highest-paid player. Ten Hag has played his small part in the resurrection of Rashford's United career after a dismal previous campaign under Ole Gunnar Solskjaer and Ralf Rangnick. and his careful treatment of the England forward showed the value of being flexible with certain individuals if they are talented enough. Ferguson knew that all too well, and former players have spoken of how the Scot would occasionally let Eric Cantona get away with certain lapses of discipline while coming down hard on other players for similar breaches.

Despite his reputation for screaming at players and his tirades being likened to a hairdryer, Ferguson knew when to use the carrot with his charges as well as the stick. Ten Hag might have been more inclined to favour the more diplomatic approach in the past, but he appears to be getting tougher.

He is still his own man, but he seems to be channeling his inner Ferguson. And that bodes well for United's future.