Below is a summary of the full article. Click here for the full version or go back to LFC Live.net

James' Park, much like Manchester United faced when Cristiano Ronaldo set his sights on Real Madrid back in 2008.

Isak, 25, has been open about his ambitions to quit the Magpies, resulting in his exclusion from the squad as the new Premier League season approaches.

In his 2013 autobiography (via The Mirror), the Scot revealed he had struck a private deal with five-time Ballon d'Or winner Ronaldo, agreeing he would stay for more season before being permitted to leave on United's terms.

An excerpt from the book read: "I found the boy expressing an urge to go to Real Madrid, and told him, 'You can't go this year, not after the way Calderon has approached the issue.'

"I said, 'I know you want to go to Real Madrid, but I'd rather shoot you than sell you to that guy now.

If you perform, don't mess us about, and someone comes and offers us a world-record fee, then we will let you go.' I had already conveyed that message to his agent, Jorge Mendes.

Article continues belowFerguson convinced Cristiano Ronaldo to stay at United for one more season despite heavy interest from Real Madrid in 2008(Image: Matthew Peters/Manchester United via Getty Images)

"I did well to calm him down.

I told him the reason I was refusing to sell him that year was because of Calderon.

He completed his 2008/09 campaign at Old Trafford before moving to Real for a then-world-record sum of £80m once Florentino Perez replaced Calderon as Real president.

The investment proved exceptional value for the Spanish giants, while Ferguson got to maintain his principles.

The duo believe Isak's off-season antics, which include skipping Newcastle's pre-season tour and training with former club Real Sociedad, have done no favours to his reputation.

Ex-Aston Villa forward Agbonlahor didn't mince his words about Isak upon learning of the recent developments, questioning: "Who does he think he is?
For more news relating to Newcastle United, visit our sister site NUFC Latest Live.