Erik ten Hag is already experiencing Sir Alex Ferguson's concerns over Cristiano Ronaldo

Cristiano Ronaldo is set to leave Manchester United this summer after requesting to move to a side that will play in next season's Champions League.

The five-time Ballon d'Or winner wants to continue playing in Europe's top competition, and despite only joining last summer, Manchester Evening News reported that Ronaldo has been left unimpressed by United's vision due to their slow start in the transfer window. Losing Ronaldo will be a huge blow, but perhaps Erik ten Hag has no choice after the disruption caused.

Ronaldo loves United, and was always dreaming of a return to Old Trafford at some point. But it's not the only time that he's rustled some feathers in the dressing room as Sir Alex Ferguson was aware of his ego back in the day.

The 37-year-old is one of the most decorated Champions League players of all-time, so it's no wonder that he wants to prolong his legacy with little years left in the game. But in order to do so, he could force a move to Premier League rivals Chelsea, which won't go down well with his adoring fans.

It's never an easy job to keep one of the best players of all-time happy, although Ten Hag hasn't even had a chance to try yet. Ronaldo is yet to train under Ten Hag as he is still yet to report for pre-season training, and it could do more harm than good should he be forced to stay.

But Ronaldo unnerved his old United team-mates during his first stint at the club, as the Red Devils were filled with huge names under Ferguson. And even for a no nonsense manager like Fergie, he made certain decisions to keep some of his stars happy to the detriment of others.

Gary Neville was Ronaldo's team-mate for six years, and the now Sky Sports pundit has never been one to shy away from the fact that he