Manchester United manager Sir Alex Ferguson fears Cristiano Ronaldo is being targeted by referees because of his extreme talent. Ronaldo was only just returning from a three-match ban following his dismissal by Steve Bennett for headbutting Portsmouth's Richard Hughes when he was cautioned by Alan Wiley for diving during the Premier League win at Everton on Saturday. Ferguson has reviewed both incidents on video and on each occasion, he feels the official clearly got it wrong. And, on the eve of Ronaldo's return to his former club Sporting Lisbon, the Red Devils chief has expressed his anxiety over the treatment his star man is receiving. 'It is a worry for us,' said Ferguson. 'It is almost as though Cristiano is being punished for his success. 'There is no question in my mind there is an unfairness about it all. 'We have looked at the Portsmouth one from another angle and it was a quite ridiculous decision. Hughes said Cristiano never touched him, so he gets a three-match ban for that. 'And the one on Saturday was even more ludicrous. Quite clearly, Cristiano was tripped on the edge of the area. Why would Cristiano go down when he can score? On that occasion, the referee reacted far too quickly.' It is clearly an opinion Ronaldo concurs with, even though, sat two feet to his manager's right, the Portugal international opted not to enter the debate. 'What the boss says is true,' said the 22-year-old. 'But I don't want to talk about referees. I only want to speak about them to my manager and my team-mates.' Ferguson's concerns about tomorrow night's Champions League Group F opener at the Jose Alvalade Stadium in Lisbon were only heightened when he was informed excitable German referee Herbert Fandel was in charge. It would be fair to conclude United have an unhappy history as far as Fandel is concerned. A trained pianist, Fandel has played all the wrong notes for Ferguson in the past, sending off Roy Keane during a stormy last 16 tussle with FC Porto three years ago before producing another red card to get rid of Paul Scholes in last season's quarter-final first leg against Roma. Initially, Ferguson buried his head in his hands as Fandel's name was mentioned, before jokingly adding: 'We need a supply of mogadon.' Whether he felt the calming drug was for Fandel or his own temper, Ferguson did not say. However, it is a fair bet he will settle for a similar performance from Ronaldo to the one he produced the last time the two sides met in 2003. Even though it was a pre-season friendly, the then 17-year-old wide man was so impressive in Sporting's 3-1 win, no lesser figures than Gary Neville and Ryan Giggs spent time on the flight back to Manchester imploring Ferguson to sign the unknown youngster. Within weeks, the Scot had done just that, the £12million outlay now ranking among Ferguson's shrewdest investments. 'It is always difficult when you sign a boy of that age,' he said. 'He has to grow and develop and also get used to living in another country, which is never easy. 'Under those circumstances, the rapidity of his rise has been absolutely amazing. 'Now we are seeing a maturity in his performance of someone in their mid-20s.' After torrid returns to his homeland against Porto and, twice, Benfica, Ronaldo is expecting a more positive reception tomorrow. Madeira-born, Ronaldo claims Sporting is his `second' home and is even still to decide whether to celebrate should he find the net for a fourth time in Champions League combat tomorrow. However, he has also warned Sporting his fondness does not translate into any willingness to go easy on his old club. 'I played here for seven years, I have a lot of friends here and I have always wanted to come back,' he said. 'I know people like me here. At Benfica they barrack me, here my reception will be good. 'I am very excited about the game and am looking forward to it so much. 'But however much I like the club, my first colours now are red and I hope to win with Manchester United.'