Roy Keane has always spoke extremely highly of former teammate Cristiano Ronaldo, who started to thrive at Manchester United as the Irishman left the club.
Despite becoming a legend at Manchester United, 36-year-old Ronaldo risks ruining his legacy with a transfer to neighbours Manchester City as the forward looks to depart Juventus.
Ronaldo is in the final year of his contract with the Old Lady and is keen on moving before Tuesday's deadline, and City have reportedly agreed personal terms with the Portuguese star.
Juventus are holding out for a £25million fee to let the star go, who they paid €100m (£88m) for back in 2018.
Keane spoke about Ronaldo in his autobiography, The Second Half, and admitted that the Portuguese has always been focused on achieving greatness; a mentality that will no doubt please City boss Pep Guardiola.
The Irishman said: "Ronaldo had an innocence to him, and a niceness. I don’t think he ever slackened off, or that he was ever more worried about the mirror than his game. I always felt that football was his love.”
However, the recent transfer revelations may have affected those views, especially as Keane has always been publicly critical on former United goalkeeper Peter Schmeichel for joining City later on in his career.
Keane has always admired the bravery of Ronaldo though, as he was impressed that the forward joined United as early as he did: “What impressed me most was that he’d been given the option of staying in Lisbon for another year, on loan, but he said no.
"He’d come over to Manchester straightaway. I thought it was a good, brave decision – because he was only seventeen."
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Keane and Ronaldo only shared the Old Trafford stage for two seasons, as the pair played together between 2003-2005, but although the Irishman has always been a difficult one to impress, this was never a problem for the Portuguese star.
He said: “After the first few days, watching him train, my reaction was, ‘This lad is going to be one of the world’s greatest players.’ I didn’t say it publicly, because I’d always be wary of building a player up too early – or knocking him down.
“He was amazing. He was immediately one of the hardest working players at United. Most of the players I knew worked hard, but Ronaldo had the talent on top of the work rate."
Ronaldo joined United in 2003 as an 18-year-old and paid Sporting Lisbon £12.25million for him, after the youngster starred during a friendly against Sir Alex Ferguson's side.
The forward automatically became United's no.7 and grew into one of the world's best, winning the Ballon D'or before moving on to Real Madrid in 2009.
It seemed Ronaldo's legacy was protected, as the Portuguese star has always spoke out about his love for United and how much he owed the side, but despite leaving as a legend, this reputation could be tarnished should he join arch-rivals City before Tuesday's deadline.
