London - Alex Ferguson has said the "formidable" Louis van Gaal is the right man to return Manchester United to winning ways once again.
Ferguson, who retired as United manager at the end of the 2012/13 campaign after a career that saw him become British football's most successful boss during more than 26 years in charge at Old Trafford, looked on as struggling successor David Moyes was sacked after less than a season at the helm.
Not only did United not win any major trophies last season, they also failed to qualify for the lucrative Champions League.
In a bid to rectify both these issues, United brought in van Gaal, fresh from guiding his native Netherlands to third place at this World Cup in Brazil and a vastly experienced club manager.
Ferguson, writing in the recently published updated version of his autobiography, said the 63-year-old van Gaal was a "good choice" for United.
"Louis, who took the job, is what I would call a managers' coach," Ferguson added. "He's one of these committed ultra-professionals. Football is his life.
"Wherever he has managed, every footballer will have learnt from him. He's strong, single-minded, as he showed again with the Netherlands at the World Cup.
"I like Louis and have always had a good rapport with him. If I had to choose one word for him it would be 'formidable'.
"His urge is to play attractive football. He likes to watch players play and players train and to be involved at all levels, including in the development of young players.
"His background at Ajax shows that his faith in youth will not diminish. He was a good choice."
Ferguson also congratulated van Gaal to make United great Ryan Giggs, briefly in caretaker charge after Moyes's sacking, as his assistant manager.
"Louis could help Giggs learn about this business. In turn, Ryan could help Louis in understanding the inner workings of United," Ferguson said.
"As I look back on all those trophies, and those 963 appearances and 168 goals, I recall him as a physical freak. How he could have performed at the level he played at for all those years is beyond me.
"With Giggs I found perfection."
The book also contained the Scot's thoughts about rival managers, including old foe Arsene Wenger who oversaw an end to Arsenal's nine-year wait for a trophy last season by guiding the Gunners to a 3-2 FA Cup final win against a Hull side managed by Steve Bruce, one of Ferguson's former United captains.
"Arsene has always been dogged and determined about his beliefs and has never succumbed to pressure to change," said Ferguson, who added the Frenchman could yet be with north London club Arsenal even longer than he himself was with United.
"The standard and the method have been consistent. He has always been good at acquiring and developing young players. He is never afraid to play young people -- which is bold, because young players are not fully formed.
"Who is to say that Arsene will not beat my record? I have my doubts, but he's having a good crack at it."
Meanwhile Ferguson reiterated his support for West Ham manager Sam Allardyce, much criticised by the club's fans for his supposedly unattractive style of football but who has since taken the Hammers into their current position of fourth in the Premier League.
"I hope that before I die, someone can explain the 'West Ham way'. What is it? They last won a trophy in 1980, the FA Cup," Ferguson said.
"I had to sympathise with Sam. He couldn't win. There is this preconception with West Ham fans that 'Big Sam' is a survivalist who tells teams to boot the ball up the pitch.
"The truth is that he stayed up with a team of very average players. That's management. He drew the best from them."