Sir Alex resigned as Man United manager on eve of treble-winning 98/99 season

Sir Alex Ferguson resigned as Manchester United manager on the eve of the 1998-99 season before performing a U-turn, a new book reveals.

The legendary boss had been in charge at Old Trafford for 12 years in the summer of 1998, but wanted to quit after a heated meeting with United's then-chairman Martin Edwards.

1997-98 had been a disappointing campaign for the club as the only trophy they won was the Community Shield and they blew a 12-point lead at the top of the Premier League table to lose the title to Arsenal.

As reported by The Times, a book published next week called 1999: Manchester United, the Treble and All That details how Edwards believed that Ferguson was taking his eye off the ball and enjoying his 'celebrity status' too much.

It is reported that when his outside interests were questioned, Ferguson responded: 'Do you want to call it a day?'.

'If you don't recognise that I am the best person to judge which players should be bought by the club, I may as well leave now,' the Scot added when he was asked about United's transfer targets.

Edwards - who is now honorary life president at United - later put his criticisms in writing to Ferguson, which is said to have led to the Scot storming into his office to confirm that he wanted to resign.

'The language Alex used was a little bit more fruity, but that was the basic gist of it,' Edwards says in 1999: Manchester United, the Treble and All That, as per The Times. The then-chairman replied: 'Well, if that's the way you feel, Alex, we'll have to accept it.'

However, Ferguson rang Edwards later that day to withdraw his resignation.

'I think what he'd done is spoken to his solicitor who'd probably said "Well, you won't get a penny on the two years left on your contract",' Edwards says in the new book.

'So, he withdrew his resignation which I was happy to do. All I wanted to do was shake it up a bit and make sure we got back on course. He'd done the Double in 1994 and 1996, won the league in 1997 so it wasn't as if he was a bad manager. It was just purely a case of "let's get back on track".

'In 1998 we had a huge lead of 11 points clear just after Christmas and we blew it. When it came to it, we still supported him with signings. But if we were going to spend that sort of money, we had to be absolutely certain that he was 100 per cent on board. And I think the combination of that letter plus the transfer buys, we did what was needed.'

United went on to win the Premier League, FA Cup and Champions League that season, making them the only English side in history to win the treble.

Ferguson would plan to quit Old Trafford again in 2001 after another falling out with the club's board, stating his intention to retire at the end of his contract.

Yet he once again performed a U-turn and stayed at the club, before eventually leaving in 2013 after a record-breaking 27-year spell as manager in which he won 13 league titles.