The last time Cristiano Ronaldo played at Old Trafford, Manchester United abandoned tradition.

In every home game, certainly in the last decade, United and opposition players have walked out of the tunnel in the corner of the Stretford End to the sound of music, usually 'This Is The One' by The Stone Roses. The handshake formalities follow, as does the Champions League theme on those European nights. Then, stadium announcer Alan Keegan reads out the line-ups, always "starting with the visitors".

Not so in March 2013. As the first 22 began to get into position, United's team was read out first, in the usual numerical order. Real Madrid's followed, starting from goalkeeper Diego Lopez and number two, Raphael Varane, until it jumped from "six, Sami Khedira" straight to "10, Mesut Ozil".

The players and officials were impatiently dithering around the centre-circle by the time the missing name was announced to the crowd. Number seven, Cristiano Ronaldo, was met with thunderous cheers.

He raised his hands to the four corners of the ground he graced for six years, where his name was held in the highest esteem even after he got the move to Madrid he spent the best part of 12 months agitating for. He made a very similar gesture 69 minutes later after scoring the winning goal that would send United out of the Champions League in Alex Ferguson's last season in charge. It was a fairly unremarkable tap-in by Ronaldo's standards; indeed, the game is mostly remembered by United fans for the contentious Nani red card and the admission from then-Madrid coach Jose Mourinho that the best team lost. But the refusal to celebrate, that peculiar yardstick by which so many supporters measure the decency of their former players, was not forgotten.

On Tuesday, five and a half years later, Ronaldo will be back again. Now 33, with five Ballons d'Or and Champions League trophies to his name, he will be wearing the number seven shirt of Juventus, for whom he has scored five goals in 10 appearances. The latest, another tap-in against Genoa on Saturday, made him the first player to reach 400 goals in Europe's top-five leagues. Neither his astonishing powers on the pitch nor his remarkable drive to be the best have waned to any real degree. "Every game teaches something," he wrote on Instagram after Juve allowed Genoa an equaliser and failed to win for the first time since they signed him.

Ronaldo's laser focus on scoring goals – something he did 118 times in a United shirt – has been as intense as ever, even in the midst of a very serious legal matter. He is facing an allegation of rape, dating back to 2009, which he strongly denies. He has carried on in his work, which he is fully entitled to do, and performed with increasing assuredness in a Juve side who are looking ever more in tune with his attacking instincts.

What remains to be seen is whether his welcome at Old Trafford will be any different this time. The disconcerting tribalism of some football fans can come to light when their favourite players are involved in any sort of alleged wrongdoing, as though club loyalties somehow have a bearing on the truth. Plus, whatever their opinion, the perception of safety in numbers inside a stadium often gives these individuals a voice, much like the semi-anonymity of social media. Ronaldo is unlikely to receive a cold reception from a crowd that once worshipped his every step, but the concern is whether the vocal backing from his most ardent fans strays into unpleasant territory. Presumption of innocence should not be forgotten, but neither should the fact that real people are at the heart of the matter.

He certainly boasts a club legacy worthy of applause. He won eight trophies there, including three Premier Leagues and the Champions League, and the first of his Ballons d'Or. As former assistant manager Mike Phelan told The Guardian: "He took the players, staff, the football club into a new dimension... he was inspirational." Things will be unsettling, though, for fans of Ronaldo, his clubs and football in general, even those distracted by a United versus Juventus game, while those legal proceedings continue.

Whether United's pre-game rituals are again restructured around their old hero remains to be seen. But Ronaldo has his own tradition at Old Trafford: scoring goals. That, at least, is something most fans expect to see again.