Manchester United striker Cristiano Ronaldo is losing one of the weapons that made him unstoppable

In his previous nine appearances against Real Sociedad before Thursday night, Cristiano Ronaldo had scored 15 goals and been on the winning side on all nine occasions.

That staggering haul includes two-hat tricks and four other occasions when he's scored at least twice against the Basque outfit. So they had every reason to be fearful of a reunion with a player they thought they had seen the back off.

But as the first half progressed at Old Trafford in United's first Europa League group game, Sociedad's defenders grew in confidence against Ronaldo. They sussed as quickly as many other teams this season that there is no longer anything to be fearful of.

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The 37-year-old is still capable of moments of divine intervention, as hat-tricks against Norwich and Tottenham this calendar year show, but they are now rarer. Whereas he once felt like a constant threat throughout a game, he burst into life only very sporadically on Thursday in a competition he'd managed to avoid for 20 years.

For all the talk about whether Ronaldo fits into Erik ten Hag's system, whether he has the fitness or inclination to press and the desire to learn new tricks, maybe this is as big an issue. He just doesn't put the fear into defences like he used to.

He ended last season in good form, but there were spells where he went goalless and he's not found the back of the net at all so far this season.

Part of the myth that made Ronaldo - and players like him - so unstoppable is that fear factor. It becomes a self-fulfilling prophecy, they reach a level where they're the best player on the planet, defences fear what they will do to them and when it happens the cycle continues.

Suddenly, it feels