Professional football should lend itself to diaries.

The normal working day ends at lunchtime. Afternoons crawl by. Once you check into a hotel you never leave except for the bus to the stadium. The mood created by Fabio Capello in the England training camp in South Africa was one of stultifying boredom. When asked how his players might occupy themselves in Rustenburg, the England manger suggested they went for a walk or read a book.

Nobody seems to have sat down with a Mont Blanc fountain pen or, more realistically, tapped some thoughts into a laptop. There have been diaries of a season that formed the basis of Eamon Dunphy's bitterly brilliant Only a Game, which confirmed what many suspect – when a footballer is out of the team, it is in his interest if the team loses.

Sir Alex Ferguson has written two seasonal diaries. The first, A Year in the Life, is perhaps the finest account of what it is like to be a football manager, from the desperate dash around Manchester for your wife's Christmas present to trying to persuade a youth-team prospect not to become a tailor. But it was written as a commission, not out of habit.

That is why the blue hardback books found in a loft are so precious. The beautiful handwriting belongs to Joe Fagan, who managed Liverpool for two years but was one of the club's bedrocks for more than a quarter of a century.

With Kenny Dalglish back in the dugout at Anfield and Bill Shankly's old traditions of pass and move gloriously back in fashion, it is perhaps fitting that these diaries should form the backbone of Fagan's biography which forms a history of the Boot Room and beyond.

Its description of the place where Joe Fagan spent much of his life is beautiful and evocative. "In time it would become furnished with luxuries like a rickety old table and a couple of plastic chairs, a tatty piece of carpet on the floor and a calendar on a wall that would later be adorned with photographs, ripped from newspapers, of topless models... there was little evidence to suggest this room was even part of a football club."

"They always call it Shankly's Boot Room but it wasn't," said his grandson, Andrew Fagan, who has co-written Reluctant Champion which comes out next week. "Shankly did not go in it. It was the preserve of his coaches, although I am sure it was 'his' in the same way a singer has his backing band."

If Joe Fagan, Bob Paisley, Ronnie Moran, Roy Evans, Tom Saunders and Reuben Bennett were a backing band, they were The Supremes. Saunders was the only one to possess a coaching certificate but between them they provided the common thread that held Liverpool together for almost 40 years.

Each man filled a specific role. Paisley was a tactician who had an eye for spotting a transfer target. Moran was an enforcer, Bennett, who was closest to Shankly, the link to the manager. Fagan, in Evans' words, was "the glue that held everything together".

Fagan, however inadvertently, could claim to have founded the Boot Room in as much as he took delivery of crates of Guinness, given as a thank-you from the brewery's team, which he sometimes coached. There was nowhere to store it, so he put it where the boots were kept and the supply of drink made it Anfield's common room.

Like Shankly and Paisley, Fagan lived modestly. "The only way you would know he was a football man was if you looked at the mantelpiece and saw the odd medal," said Andrew. "You'd sometimes stumble across a massive bottle of champagne or Bell's whisky from his manager-of-the-month days." Paisley's house was awash with the stuff.

"The diaries began as training manuals. They would never, ever have used the term sports science but it almost is. They noted every training session. And, if a player pulled a hamstring, they could cross-reference to the conditions or the pitch and see if there was a connection.

"Both Bob Paisley and my granddad trained as physios and they took that part of it very seriously. Kevin Keegan told me that when he picked up an injury shortly after buying a new car, Bob and my granddad almost literally took the car apart looking for reasons why he had a strained hamstring. They became convinced it was to do with the clutch. That's how much detail they went into.

"As his career went on the diaries became more expressive and contained more of his thoughts. As a manager he was slightly pessimistic. I think they all were to a certain degree, which I put a bit down to them having been in the war.

"They expected things to go badly and were pleasantly surprised when they didn't. Paisley was very much

the same. Outwardly, to the Liverpool public, they were constant optimists but not in private."

It was while Paisley was manager that Fagan's influence grew. By Boxing Day 1981 the regime seemed gripped by crisis. Liverpool had lost the championship to Aston Villa in May and a 3-1 defeat to Manchester City at Anfield saw them fall to 12th.

Fagan recorded in his diary: "Dismal, not up to the standards we require. I would say two blokes in our team are playing to their ability. The rest? No."

On the Monday at Anfield he tore into the team. The tirade was so powerful because Fagan was rarely angry. Gary Neville said the Manchester United dressing room could expect to receive the full Ferguson hairdryer treatment around three or four times a season. Any more and it would start to lose its impact.

Sometimes, Fagan could sense things going wrong. In 1977 Liverpool might have won the Treble had they not lost the FA Cup final to Manchester United. "Training was bloody awful," Fagan noted before they travelled to London. "The lads had two meetings about [personal] arrangements for Wembley and then came out expecting an easy-osey time. They didn't get it. I bollocked them and told them it was football that counts not bloody tickets."

"He didn't really want to be manager," says Andrew. "He didn't want to let anyone down and he knew, too, that if someone else had come in, they might have brought in their own backroom staff. The Boot Room might have gone and these were the people he had closest in his head."

His diary for his first day as manager in 1983 is disarming. "Nothing startling happened," he wrote before turning his attention to his first press conference. "Don't know whether I said the right things but I tried to! I have got to get used to it but I have said this before, what appears in cold print isn't necessarily what you actually say."

Andrew says: "When he did become manager some of the things he was concerned about and mentioned in his diaries – like dealing with the press – faded away. He was better at it than he expected. He played it quite well. He wasn't that comfortable with being in the manager's office after everyone else had gone home. It was then that he felt the sense of responsibility, the difference between being the assistant and the main man."

It was especially true of his wearing, sandpaper-like relationship with Craig Johnston, although there were some advantages to being promoted from assistant. "When it was announced my granddad was going to become manager, Graeme Souness got the players together and said: 'We are not going to let this man down. Nothing is going to go wrong this season'. And it didn't."

There are two photographs in the book that sum up Fagan's two seasons at the helm. The first is the one with him sitting by a swimming pool in Rome, with the 1984 European Cup at his feet, like an Oscar-winner in Beverly Hills.

Then there is the one of him arriving at Speke Airport, a year later, his face dissolving into tears after the other European Cup final in Brussels, unable to cope with the knowledge that 39 – mostly Juventus – fans had been killed in what was his final match as Liverpool manager.

He had been exhausted by the two years at Anfield – Mark Lawrenson said he suddenly looked very old as Liverpool, without Souness, made an insipid defence of their title. He had asked to step down before Heysel, a match that cast its long shadow over him.

"He found it incomprehensible. He lived with it all it his life," says his grandson. "He had served in the Royal Navy during the war, he understood what was a game and what was not. From what I am told he never really talked about it at home, he simply carried it with him."

The shame was all-consuming at a time when unemployment on Merseyside stood at 25 per cent. These were the years of Boys from the Blackstuff; of Julie Walters' plaintive cry in Educating Rita: "There must be other songs to sing"; of a city turning in despair to the sleek, suited gangsters of the Militant Tendency.

Due to the times, attendances at Anfield were significantly less for the Treble season of 1983-84 than they had been in 1958-59 when Fagan joined a Liverpool rusting in the Second Division. The quality of the football in Liverpool had risen above it. From 1978-1989, which roughly coincided with the years of Margaret Thatcher's Britain, the championship left the city only once. That pride was cracked by Heysel.

It is, however, the previous season – 1983-84– for which Fagan should be remembered. Dalglish says it is easier to win the European Cup now than it was before it became the Champions League. You had to win your own championship to enter, which would have debarred all subsequent English teams from European Cup finals bar Manchester United in 2008. And there was no safety net of a group stage.

English clubs had less money. In 1984 Souness could set himself up for life with a transfer to Sampdoria, who had finished seventh in Serie A. The semi-final was against Dinamo Bucharest, a club that would provide little resistance to the champions of England now but who offered bitterly effective opposition then. Liverpool was a more modest place. When they won the championship in 1984, a box of medals arrived at Melwood and Fagan walked round with them saying: "If you've qualified for one, help yourself."

When it came to the penaltyshoot-out against Roma to decide the European Cup in their opponents' own stadium, Fagan simply asked if anyone fancied taking one. He even asked Dalglish, who coolly informed him that he had been substituted.

It led to two men volunteering whom nobody wearing red in the Stadio Olimpico believed should have taken one – Steve Nicol, who thrashed his over the bar and Alan Kennedy.

The final entry for the momentous 1983-84 season is recorded with typical modesty in the hard-bound blue notebook. "Rome: European Cup final. Won on penalties 4-3. What can I say? Won the big one as they say and rightly so. We were the better team; we just couldn't score.

"Alan Kennedy made us champions with the best penalty he has ever taken. In conclusion, let me congratulate Ronnie Moran, Roy Evans and the rest for their magnificent efforts. Well done the lads. J.F.F"