Alex Ferguson hailed Walter Smith's contribution to football as "immense" after the former Rangers and Scotland manager died at the age of 73 on Tuesday.
Legendary former Rangers manager Walter Smith dies, aged 73
Former Rangers and Scotland manager Walter Smith died, aged 73, on Tuesday
"It is with profound sadness that we announce the passing of our former manager, chairman and club legend, Walter Smith," Rangers said in a statement.
Smith is the Glasgow giants' second-most successful ever manager, winning 21 trophies across two spells in charge.
Already at the club as assistant to Graeme Souness, Smith was appointed full-time manager at Ibrox in 1991 and won seven league titles in eight years to lead the club to a record-equalling nine consecutive Scottish league titles.
After a four-year stint at Everton and a brief spell as Ferguson's assistant at Manchester United, he was appointed manager of Scotland in 2004.
"I am absolutely devastated," Ferguson told the Manchester United website. "He was a great friend of mine for years and years.
"In all that time you were dealing with a man with great moral compass in how he lived his life and the friendship he offered so many people.
"His contribution to football with Dundee United, Rangers, Scotland, Everton and Man United was immense."
In 2007, Smith returned to Ibrox, winning three more league titles and guiding Rangers to the UEFA Cup final in 2008 before retiring in 2011.
"It is almost impossible to encapsulate what Walter meant to every one of us at Rangers," said Rangers chairman Douglas Park.
"Winning 10 top-flight titles as manager, five Scottish Cups and six League Cups, as well as leading his club to the UEFA Cup Final in 2008, he will be remembered by the football community across the world.
"His spells as Scotland manager as well as managing in the English Premier League underlined his credentials as one of the great modern day football managers.
"However, for Rangers supporters, he was much more than just a football manager. Walter was a friend to many, a leader, an ambassador and most of all a legend."
Smith's playing career as a defender at Dundee United and Dumbarton never hit the heights he would go on to enjoy in management.
His coaching journey began as assistant to legendary former Dundee United boss Jim McLean before spells as Scotland's under-18 and under-21 manager.
Smith also assisted Ferguson as Scotland boss at the 1986 World Cup.
But it was at Rangers where he made his name.
After five years as Souness' assistant, the latter's return to Liverpool handed Smith his chance to take the top job at Ibrox.
He signed the likes of Paul Gascoigne and Brian Laudrup as Rangers dominated Scottish football for nearly a decade.
Smith's time at Everton was less successful as he battled for four seasons just to keep the Toffees in the Premier League.
“He was one of the very best people I was lucky enough to meet in my lifetime in football," said Everton chairman Bill Kenwright.
"A man of loyalty, integrity and great talent. Strong when he needed to be but with a mischievous sense of humour that could ease even the most tense situations."
His close relationship with Ferguson endured and the two linked up again towards the end of the 2003/04 season as United won the FA Cup.
Smith lost only four of his 16 games in charge of Scotland, but even a bright start to qualifying for Euro 2008 could not resist the lure of a return to Rangers in 2007.
Rangers reached the UEFA Cup final in his first season back, losing 2-0 to Zenit St Petersburg in Manchester.
But they bounced back to win three consecutive league titles before Smith retired and handed the reins to his assistant Ally McCoist.
Ranger's fierce rivals Celtic also paid their respects to what they described as a "tremendous servant to Scottish football."
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