Alex Ferguson, Ally McCoist and Kenny Dalglish were among those to pay tribute to Walter Smith on Tuesday after he died aged 73.

Smith - who enjoyed much of his playing career at Dundee United - is a Rangers icon, having won 21 trophies during two spells at Ibrox as manager of the Scottish champions.

He oversaw the Glasgow giants' unlikely run to the UEFA Cup Final in 2008 and managed Scotland between 2004 and 2007.

Smith also took charge of Everton and spent time at Manchester United as an assistant to Ferguson, who expressed his sorrow following the passing of his friend and former colleague.

"I am absolutely devastated," Ferguson told United's official website. "Walter was a special person. He fought his illness with great courage.

"He was a great friend of mine for years and years, I had him as my assistant at United in 2004 and he was also my assistant when Scotland went to the World Cup in 1986.

"In all that time you were dealing with a man with a 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."

McCoist, who won 10 Scottish Premiership titles with Smith as both a player and later an assistant manager, gave a moving tribute to his friend and ex-boss.

"He means everything to a lot of folks, myself included," McCoist said to talkSPORT. "He was my boss, my coach, my second father and then turned into one of my best friends

"I could sit here and tell you about Walter Smith until the cows come home, about how good a manager, how good a coach, how good a football man he was.

"The one thing Walter was, he was 100 per cent honest and fair. If he said something to you, he wasn’t saying it for effect, he was saying it for a reason. He was saying it because it had to be said.

"He was just the most genuine of men. He was hard, fair, honest and he had an absolutely wicked sense of humour. He was just brilliant to be around."

Fellow Scotland great and Celtic rival Dalglish paid tribute to a "truly great man", while Liverpool defender Andy Robertson expressed his heartbreak at losing "another great of Scottish football."

"Marina [Dalglish's wife] and my heartfelt sympathies are with Walter’s wife Ethel & his boys," Dalglish posted on Twitter.

"Though we were on opposing sides on the pitch, he was a real footballing friend off of it.

"He was respected by all and one of the few able to transcend rivalries. Today we have lost a truly great man. RIP."