The sharpest minds in Houston can guide shuttles but have no business with fallen stars. The problem of Cristiano Ronaldo is therefore one Roberto Martinez must solve alone in this corner of Texas.

Alone might be the operative word there, if conspiracy theories are to be believed around a Portuguese squad that has lost patience with an ageing passenger.

On Tuesday, they face Uzbekistan at the same stadium where, last week, Ronaldo did so little to suggest the tides of time can be bent to his will. He was poor against the Democratic Republic of Congo and those around him seemed exasperated for reasons beyond the setback of a 1-1 draw.

And that is the key point. Because Portugal possess enough talent to win this World Cup, but they are saddled by two questions: W here does the line fall between indulging Ronaldo and harming their own chances? And will Martinez ever have the courage to act when he appears so wedded to the path of least resistance?

Uzbekistan might not offer the ultimate testing station for this issue. They qualified well and put up a fight against Colombia, but aside from Manchester City's Abdukodir Khusanov have no presence in Europe's top five leagues. If Ronaldo makes an impact here, it won't be a surprise.

But if he doesn't, Martinez will surely accept there are no more justifications for a player who looked desperately ineffective at Euro 2024 and whose goals in Saudi Arabia are an unreliable currency. At 41, his narrative has moved beyond the romance of a last dance and dangerously close to the realms of delusion.

Against Congo, Ronaldo managed no shots on goal, no key passes, no dribbles, no tackles, no interceptions and 12 fewer touches than his own goalkeeper in a game where Portugal had 75 per cent possession. Covering only 7.4km in 90 minutes, he ranked third from bottom of all outfield players in the first round of games, which was more than Lionel Messi and minus the hat-trick.

Uzbekistan could offer an upturn on Tuesday. But the most relevant details to study will involve Ronaldo's interactions with team-mates on the pitch, because those dynamics appear to be changing.

'Civil war' has been highlighted as a 'risk' by Portuguese media, siblings have got involved on social media and a comment from Joao Neves, post-Congo, that his captain is 'just another player' has been analysed, dissected and clarified like a matter of state importance. United fronts have been erected in defence against any notion of rebellion.

Spotting truths amid so much noise is no straightforward task, not least because any frustrations from Portugal's gilded rank and file would be so easy to believe.

Yet there has been a distinct shift in behaviours at this tournament. And certainly in comparison to the last one, in 2024, which was notable mainly for how Ronaldo's team-mates prostrated themselves in service to his aura. That was best shown in the awkward moments after Ronaldo delivered a routine assist to Bruno Fernandes against Turkey and drew celebrations away from the scorer and towards himself.

It was a faintly ludicrous scene and one made dafter when Martinez later eulogised the act of a basic pass to a better-placed team-mate – he said it 'should be shown in every academy in world football'. While Martinez has evidently carried that level of deference to the United States, the tolerance for Ronaldo among his fellow players is open to scrutiny.

That was hinted last Wednesday, when he snatched a chance from the boot of Fernandes and missed the target altogether – Fernandes gesticulated at Ronaldo before slamming a fist against the turf and, behind him, Nuno Mendes screamed at the sky. Those in-the-moment reactions have always existed, but rarely in the court of Ronaldo.

Tangential? Maybe. But the murmurs of division are growing, elevated by Ronaldo's own sister, Katia Aveiro, after that 1-1 draw. 'They magically forgot how to pass the ball, how to win the ball, how to counter-attack,' she wrote on social media. 'The game rolled from midfield backwards. This World Cup is strange.'

If the tacit suggestion was that Ronaldo had been ignored, then Aveiro was supported by the figures. Her brother received only 22 passes in 90 minutes. Vitinha and Neves almost exclusively favoured shorter balls to Fernandes rather than a target of limited movement further in front.

But what Aveiro cited as a problem might, conversely, be taken as a big step in the right direction for the team – neutral observers know too much of Portugal's play has been channelled through Ronaldo in the years since his astonishing peak. Even in this twilight, he has demanded it and pouts when his needs are not met.

In a squad featuring the likes of Fernandes, Neves, Vitinha, Bernardo Silva, Joao Cancelo and Ruben Dias, that is plainly absurd. And now the early signs here are that more independence has gone into the team's thinking; if they concluded there are already enough Ronaldo statues in this world – New York, Madeira and Goa – then who would blame them for objecting to one in living form on the pitch?

That is possibly unkind to an all-time great, but when a World Cup is on the line, there must be a limit.

We should add, though, that the solution isn't as simple as dropping Ronaldo, because who would replace him? That's not where Portugal's depth lies. Goncalo Ramos remains the most logical choice, but more than half of his PSG appearances last season came from the bench. He scored 11 goals; Ronaldo got 30 in 37 in Saudi Arabia. Irrespective of opposition, Ronaldo remains a world-class finisher. Uzbekistan might yet add to his considerable list of victims.

But the issue is what he costs in movement, patterns of play and team balance. That is not a new development; just a deteriorating state of affairs. None of the squad will freely admit it – the social media backlash against Neves this week was remarkably hostile, and also to his girlfriend, the actress Madalena Aragao, who was victim of a fake post in her name that criticised Ronaldo. Among those to reply with some aggression was Ronaldo's fiancée, Georgina Rodriguez. Prior to being deleted, it translated as: 'Wow! This generation is coming through strong!'

Such are the fevered emotions around an icon of near unprecedented fame and loyalty from his fans.

But the time for the new generation arrived, respectfully, several years ago. That may or may not be clear against Uzbekistan in Houston but, if it is, Martinez will have to find a way to bring Ronaldo back down to Earth.

So far, it is a problem that appears beyond him.