During his reign as Manchester United manager, Sir Alex Ferguson got very few decisions wrong. The Scotsman won 38 trophies as Reds boss, including 13 Premier League crowns, five FA Cups and two Champions League titles. When he signed a player, they usually excelled, and when he sold a player, they often didn't.
There are, of course, certain players who thrived after being sold by Ferguson. Jaap Saam, who was prematurely sold to Lazio in 2001 after three successful seasons with the Reds, enjoyed an impressive career after leaving Old Trafford. The Dutchman's relationship with the United manager had soured, but a transfer still could, and probably should, have been avoided.
Another player is Paul McGrath. The Irish defender, who signed for United in 1982, flourished under Ron Atkinson, and it did not take him long to leapfrog Gordon McQueen to become the regular partner to Kevin Moran at the heart of the backline. Despite winning the FA Cup in 1985, the Reds should certainly have won a league title during that period. The fact that the club had not, coupled with an underwhelming start to the 1986/87 campaign, ultimately saw Atkinson sacked as manager.
He was, of course, replaced by Ferguson. For McGrath, he remained a regular member of the first team for that season and the following campaign, but he began to struggle with knee injuries. As a result, he started to feature less under the Scot and fell down the pecking order, behind new signings Steve Bruce and Mal Donaghy.
McGrath's relationship with Ferguson, despite promising to be a fruitful one, quickly became strained. The United manager lost patience with the Irishman, as well as his teammate Norman Whiteside. The management styles of Ferguson and Atkinson were incredibly different - and it was something that the Reds defender found difficult to come to terms with.
It was in a cramped away dressing room at Moss Lane that the pair famously clashed. Ferguson, who had picked a makeshift XI for a clash against Altrincham, was just inches from McGrath's face as he unleashed a torrent of abuse at half-time.
"WHAT ARE YOU DOING PASSING THE BALL BACK?" Ferguson roared at McGrath.
Given that it was *just* a friendly, the Irish defender was not prepared to sit there - next to his teammates and friends - and be part of the infamous hairdryer treatment.
"I said, 'Shhh! I can hear you. Calm down, calm down'. At that stage I was really going to say, if you want to duke it out we can do it!" he told MEN Sport.
"I was so upset because I was being belittled. To be picked out because I made one mistake in the whole of the first half annoyed me and then I started standing up for myself, but I should not have done it in front of the kids. That made me feel ill about it afterwards."
Their relationship appeared to be beyond repair, and Ferguson went on to offer McGrath a retirement package of £100,000 - with a testimonial in Dublin forming the remainder of the deal. While the defender was just 29, his injury problems and off-field issues had been well-documented.
McGrath, having made just 69 appearances for the Reds, rejected the offer and left Old Trafford in 1989 after seven years with the club. He was a fans' favourite and, at that point in time, one of the best defenders in England. His move shocked supporters of the club, but the player probably saw it coming. Ferguson sold the defender to Aston Villa, while his great mate - Whiteside - joined Everton.
"When I was injured, at certain times, it was easy for myself and Norman just to look at each other and say, 'What are we going to do after training?' The easy answer was, 'Well, we will just go out and have a couple of pints and relax', and it did get out of hand," McGrath added.
"Ron [Atkinson] used to get told we were doing it from time to time and he would slap us with fines and stuff like that. Sir Alex had a much more domineering personality and rightly so because he knew where he wanted to take the club.
"As the older partner in the partnership I don't think I had a clue - only that I was going on one trek - and I was advised early on that I was not really wanted at the club because I was hell-bent on doing what I wanted to do.
"I like Sir Alex an awful lot for the way he treated me, I genuinely do, even though he treated me the best way for Manchester United - not for Paul McGrath."
In his autobiography, McGrath suggested that he felt like he was constantly being 'monitored' by the stern Ferguson. The Irishman also felt that the Scot didn't 'rate' or 'trust' him. Ferguson, however, disputed this. He insisted that his only goal was to restore United to glory and in order to do so, he needed to revamp the squad and improve the standards.
However, in his book, McGrath titled the chapter about Ferguson 'polar opposites' - a perfect example as to why the pair were just never going to work at United.
The Irish defender thrived at Villa Park after leaving United, winning the PFA Players' Player of the Year award in 1993. He made over 300 appearances for Villa and was part of the side that won the League Cup in 1994 - when they beat United in the final at Wembley.
Unlike Ferguson, Villa managers, such as Atkinson and Graham Taylor, were more patient with McGrath. They simply took a different approach to managing the player. However, despite their differences, McGrath still held Ferguson in high esteem, and while it was difficult on a personal level, he understood that the Scot had a job to do at Old Trafford.
"I still had loads of respect for him," McGrath told JOE. "He was one of those people who was going to make Manchester United brilliant, I thought. Gordon Strachan kept coming up to me saying, 'Paul, you want to be a part of this, you really do, because he is the real deal'.
"And I kept saying, 'Well, I thought Ron was the real deal'. I just thought, 'I may as well do things my way'. And doing things my way, I was out about a month and a half later. I accepted it as well...
"He wasn't a vindictive person, he just wanted things to be right for Manchester United."
While it took a while for McGrath to be willing to bury the hatchet with Ferguson, he eventually came around to the idea of rebuilding his relationship with the legendary boss.
"I wanted to apologise for the way I had spoken to him and had that thing on my mind," he told MEN Sport. "I had never spoken to another manager that way.
"I had never said shhh to anyone, even when I did get barked at, so that was playing on my mind but after '94, I think it was the League Cup final, he just came up to me and gave me a big punch in the chest and said, 'Well done big man'. I just said, 'Thank you very much'."
As well as this, McGrath - after retiring from the game in 1998 - was offered a job at United by Ferguson. The Irishman provided pre-match entertainment in the executive suites at Old Trafford. According to the man himself, that kind gesture helped mend the relationship between the pair.
"To be fair to Sir Alex, he was brilliant because I got a job when I was finished football, I got a job down there and he was an absolute gentleman," he told JOE. "He rang me and said, 'Paul, do you want to come down on Saturdays and we have lads that go around the tables just chatting to anyone who wants to chat to them and then you go up and talk with a comedian.'
"By the way, the comedians were doing most of the work. They'd ask questions and they'd lead you into telling stories. Well, I was one of the worst people to do that job. Alex used to meet me walking in, shake my hand every time. He would always have a smile and an arm around the shoulder and stuff like that.
"He used to say, 'How are coping, son? You'll get better at this', and he was so supportive. I grew to like him a hell of a lot more than I ever did."
Although Ferguson's decision to sell McGrath didn't make sense to a lot of people at the time, the Scot was, ultimately, vindicated. The Reds went on to dominate English football under the manager, while the Irish defender enjoyed the best form of his career at Villa.
It is, however, important to note that Ferguson never once doubted the player's talent. In fact, the manager's description of the Irishman perhaps tells you all you need to know about McGrath.
"He was an exceptionally skilful and stylish defender, with marvellous innate athleticism, a man whose abilities stood comparison with any central defender in the game," Ferguson once said.
While he is part of a small group of players who thrived at another club after being sold by the Scot, Ferguson knew that the defender needed to be at another side to succeed - and after many years, McGrath somewhat understood that.