He was on the world stage in front of a global audience. He was the last Englishman standing at the World Cup, given we had lost to Argentina a few days before. And what did Robbie Williams, the former Britpop bad boy, manage to do? Almost become a national embarrassment.

No, I’m not talking about his performance of a song called Desire, the official Fifa anthem which no one knew the words to, alongside Laura Pausini (me neither) and Nicole Scherzinger.

I’m referring instead to the now-viral moment, during a live interview, when a speck of something white and granular appeared to drop out of Robbie’s nostril or perhaps his mouth, and – plop! – land on the head of his microphone. Barely missing a beat, the former Take That singer swiftly used his fingers to pick the ‘object’ up, before rubbing his face, meaning the white speck ended up on his forehead.

Was the reformed addict – it was none other than Elton John who forced him in to rehab more than 25 years ago – back on the marching powder again? Had he let the side down?

The morning after the faux pas seen by millions, Robbie posted a short video on Instagram where he appeared to be ashamed, humble – and, did I detect, perhaps a little worn out?

Robbie Williams during his performance of a song called Desire, the official Fifa anthem, with Laura Pausini and Nicole Scherzinger

‘Just like to apologise for the object that fell on to the microphone yesterday. It was deeply unprofessional and people worried about me. But it is OK because I had several more.’

He then opens his mouth to reveal two mints on his tongue, before giving his trademark cheeky-chappy grin. Was he being honest or merely... TicTactical?

We all love Robbie, of course: he’s the flawed, chaotic, talented rogue who has bravely admitted struggling with rampant addiction to heroin, cocaine and alcohol in his twenties, leading to near-fatal overdoses.

‘I was ingesting everything I could get my hands on – ecstasy, cocaine, drinking,’ he said last year. ‘I’m literally drinking like a bottle of vodka a night before going in to rehearsals, so that’s happening every night.’

Robbie has said he has now been sober for a quarter of a century but his long-suffering wife, American actress Ayda Field, has spoken about the impact his addiction has had on family life. Having enjoyed a renaissance with a recent Netflix hagiography that earned him a few new fans in the US, if Robbie was ever shown to have tragically relapsed, the fall from grace in the country he still wants to conquer could be career-ending.

The now-viral moment, during a live interview, when a speck of something white and granular appeared to drop out of Robbie’s nostril or mouth

Barely missing a beat, the former Take That singer swiftly used his fingers to pick the ‘object’ up, before rubbing his face

The best way to disarm any brewing scandal is to be self-deprecating. Humour is the most effective weapon to take the wind out of any squalls on social media, and I can only imagine the frantic phone calls from his handlers, PR managers and record company executives after Robbie’s white-blob video went round the world.

His minty-fresh video did just the job.

On close examination of the original footage, it’s hard to see definitively if the object did indeed escape his mouth. The jury is divided online: many of his fans instinctively believe him, while others have posted memes of polar bears nose deep in snow or a pair of pants on fire.

Many US viewers, who’ve never sung along to Angels on the car radio, were baffled by the presence of this anonymous Briton at the final in the first place.

But let’s take him at his word. Everyone is too swift to outrage these days, and Robbie deflated the self-righteous balloons of condemnation in his typical inimitable way. If he ever does relapse – and let’s pray that never happens – he will need our help and our sympathy.

But all that said – it’s not a good look for anything to be flying out of the mouth of a 52-year-old man. I know Robbie loves to be glib, but he really needs to be much more circumspect – and learn some manners while he’s at it.