News From Manchester: Manchester United have trump card in Cristiano Ronaldo transfer stand-off – Richard Fay

That Ronaldo arrived at Carrington accompanied by agent Jorge Mendes on Tuesday proved that he meant business, and that his representative would be their to argue his case for a transfer this summer.

Ronaldo, 37, wants to leave because he has a desire to spend his final few seasons playing in the Champions League, a competition he still sets the standard in and lit up with six goals in six appearances last season.

Uniteds failure to finish in the top four has not only cost their star striker the chance to play in the club competition he cherishes most, but it has also led to a salary reduction of 25 per cent, a clause triggered in his contract after their sixth-place finish.

One of those situations would be bad enough, but for them both to occur at the same time is unacceptable on the players part, and he doesnt think he should be the one punished when he saved the side so often last season.

In a strange way it is testament to Ronaldos extremely high standards that he doesnt want to waste another precious year of his career at a side so unpredictable, though his desire to leave and the way he has gone about it certainly hasnt gone done well with fans.

But this is a man who likened himself to a slave when he pushed to leave United for Real Madrid in 2008, and will always put his own personal success ahead that of the teams he plays in. His personality flaws have always been waved away as evidence of his desire to win, rather than criticism of his character.

This summer he and Mendes are looking to pressure United into selling again, but the truth is there is little market for the veteran forward and United, most importantly, have no reason to sell their star striker who still brings with him incredible commercial gains.

The other issue for Ronaldo is the upcoming World Cup in Qatar and his deep desire to win the only prize in world football that still eludes him.

Ronaldo is yet to train with his teammates this summer and, despite his own intense individual training routine, soon he will be lacking the match sharpness required to keep him at his peak physical fitness for his international commitments with Portugal.

With no obvious suitors for Ronaldo, United are in the driving seat and with the club in no need to grant his wish of an exit they have little to lose by keeping him around, other than the risk of him unsettling some of his teammates.

But with Ronaldos main aim winning the World Cup this winter, he might need to accept that his best chances of doing so come with playing regularly, even if that means doing so for a United side in transition.