If you fail to prepare, then you should be prepared to fail. Alex McLeish knows that only too well at Ibrox.

The glory of a domestic clean sweep didn't last long in the summer of 2003. Rangers had been dominant but they were soon decimated.

McLeish had written his name into the history books but the future was soon bleak as he prepared to defend the haul of SPL title, League Cup and Scottish Cup that was won in such dramatic and emotional circumstances.

One by one, he had to say farewell to the heroes who had allowed him to live his dream. Barry Ferguson and Lorenzo Amoruso signed for Blackburn Rovers, Neil McCann left to join Southampton and Arthur Numan, Claudio Cannigia and Bert Konterman also moved on.

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Those that replaced them were simply not up to the task. Come the end of the campaign, Rangers had lost their grip on all the silverware and McLeish was back at the drawing board once again.

Two decades on, the current Ibrox incumbent will know how he felt. Rangers do not have the titles and trophies to defend next term but they will have a significant overhaul during the summer.

This opportunity is the one that Michael Beale has been waiting on for some time now. It is a chance that he must make the most of now that a squad and a side will be assembled in his name and with considerable backing from the Light Blues board.

"When we won the Treble, there was then a mass exodus," McLeish said. "We brought in a lot of players. On names, they were tremendous.

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"But maybe they just didn’t have the legs any more. That was kind of what thwarted us that season.

"Recruitment is massively important. That’s Michael’s next biggest task. Bringing in athletic guys – guys with speed.

"Because, let’s be honest, at the top level – and you see it with the national team now and in the Premier League – everybody is very quick.

"Rangers need quick players but they also need quality. That’s where you have to show how good you are in recruitment."

McLeish knew that he couldn't afford to make the same mistake twice as he turned his attentions to the 2004/05 campaign. A silver lining emerged from the dark clouds.

The Herald: Alex McLeish

Dado Prso, Alex Rae, Marvin Andrews and Jean-Alain Boumsong arrived on Bosman deals. Gregory Vignal was a loan signing from Liverpool and Nacho Novo secured a bargain switch from Dundee.

The League Cup was won with victory over Motherwell in March but it was the SPL triumph that was the ultimate redemption and reward for Big Eck as his planning paid off and a summer of significant alterations proved to be the starting point for success at Ibrox.

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"It’s very difficult," McLeish said about the process of making widespread changes to a squad inside one window. "If you know who you are bringing in and do the work in advance, that’s definitely key.

"If you fast forward in my time, I spoke to David Murray and said we had to get players early [in the summer of 2004]. I was scouting Dado Prso in the semi-final of the Champions League the season before.

"He absolutely battered Porto, even though they went on to win it. It was no-brainer to bring in the big man.

"Alex Rae was a free transfer, a good quality player who you knew still had some legs in him.

"So when you do your homework early and your preparations early, it makes a difference.

"After the Treble, we kind of did it in a week before the start of training. It was very difficult."

The champions that were crowned in 2005 at Easter Road were not expensively assembled. It was a case of Rangers spending wisely rather than lavishly as McLeish's eye for a player and a person came to the fore.

Boss Beale must now prove that he has that same ability as he continues to work his way through his list of targets this summer. The results so far has been positive at Ibrox and the departure of Ange Postecoglou could prove to be an added bonus for Beale.

McLeish said: "Obviously getting Dado was a free transfer and one or two others who were out of contract, that saved us spending a fortune. It was just wages, although they were still pretty high.

"But yes, absolutely. Michael will now be judged on the guys who are coming in and how well they do and how good their recruitment was, so that is big for him.

"That is going to be difficult [to build a title winning squad in one summer]. But at the same time there is now a wee window with the fact that Postecoglou has left Celtic.

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"Celtic have to re-evaluate, rebuild – maybe not rebuild – as they have the players, they don’t have to sell anyone. They have great players.

"If it’s not broken do not fix it, when the new coach comes in. But it is certainly a wee window of opportunity."

The deal that has taken Postecoglou from the east end of Glasgow to north London could, McLeish believes, unsettle Celtic at a time when many would have expected them to pick up where they left off next term.

The appointment of the next Parkhead boss will naturally have a bearing on Rangers' ambitions and fortunes as Beale gears up for his first full campaign back at Ibrox and a proper crack at the Premiership title in the coming months.

The Herald: Michael Beale

His maiden season in the dugout was certainly an eventful one but the trials and tribulations experienced and lessons learned should stand the Englishman in good stead this summer and beyond.

"I actually went to quite a lot of QPR games because a friend of mine has a box there and he invited me to a lot of games," McLeish said.

"There was a tremendous start and then a bit of a dip but these are lessons that great men have to get before they become giants in the industry. I am sure Michael has learned a lot in those couple of years that he has been a manager."

*Alex McLeish was promoting Viaplay’s live and exclusive coverage of Norway v Scotland and Scotland v Georgia. Viaplay is offering a special limited-time offer for Scottish football fans available until June 20th only. Visit viaplay.com for more information.