Booing was evident as Sebastian Vettel stood atop the Belgian Grand Prix podium.
The reason was obvious, too. At least for a moment. Formula One media and fans alike nodded sagely: the Red Bull Racing driver is not a popular man with the fans.
But then, as a second thought, a further possibility emerged. Environmental group Greenpeace's PR pre-and-post-race protests against Shell.
Ah, maybe it was not as clear cut as first considered.
Greenpeace's stunt involved deploying previously-hidden, radio-controlled banners on the podium balcony, on which the "SaveTheArctic.Org" web address read, with a logo similar to the start-finish straight banner (put up immediately prior to the start) emblazoned with: "Arctic Oil: Shell No!"
So, the anger of the crowd was perhaps not meant for Vettel after all. Their disapproval, hindsight suggests (along with video/audio from the podium ceremony) was directed at Greenpeace's display against Belgian GP title sponsor Shell's action in the Arctic.
Never mind, then. Well, not exactly.
That Vettel was thought to be the subject of booing is a fascinating case study in driver appreciation.
He was booed in Canada after a dominant victory, and again there were suggestions of jeering in Hungary after venting his immediate frustrations at Kimi Raikkonen's defence of second place.
The assumption from the majority was that it was happening again. And it says a lot about how Vettel is perceived that we so readily assumed he was being booed.
There's no questioning the German is a worthy triple world champion. Try as you might to dull down his achievements by virtue of his seat in the best car on the grid, only very good drivers can win the world title, and only the greatest can boast multiple crowns.
He's also a fantastic ambassador for the sport. Those who witnessed his appearance on the British television show Top Gear can vouch for a brilliant sense of humour.
It's also harsh to suggest such character is merely for show. His amiable personality is very much in evident on Grands Prix weekends. Few drivers share a joke, or make light of press interviews, like Sebastian Vettel does.
Ah, then it must be his behaviour on track. The arrogance he holds within the team, the dangerous approach he takes to battling with rivals.
How can fans love a driver who shoves his fellow competitors off-piste at 160mph (Monza, 2012)? How can fans love a driver who manipulates circumstances for split-second gains?
Such fans might recall another German world champion, who was around not too long ago, who did exactly that. In fact, Michael Schumacher's legacy is as much down to him being a Marmite character as it is his 91 victories and seven world titles.
Vettel is a victim of his own success, as much as he is his behaviour. He's no People's Champion. His team is regularly producing a pace-setting car, while "fan-favourites" such as Fernando Alonso and Lewis Hamilton are regular podium visitors but only able to fight for victory on occasion.
He's also been chastised for the "finger" salute after successful qualifying efforts of race triumphs, is a ruthless character on the track and—for some—a frustratingly likeable character off of it.
And it's very likely a number of fans have yet to forgive him for events in Malaysia, not least because that did happen with a fan-favourite, in Mark Webber.
Vettel's a champion you love to hate. In many ways, he's a modern-day Alain Prost. Comparing the driving ability across generations is a dangerous and rather futile, but comparing style and popularity is not.
Like Prost, Vettel has found himself in race-winning machinery more often than not—and has done since his career's formative years (save for one season at Scuderia Toro Rosso, much like Prost and the uncompetitive McLaren team in 1980). Even then, Vettel won a race.
He's mighty fast, unstoppable when the car is working perfectly and is also not afraid to manipulate circumstances for split-second gains.
If you're a conspiracy theorist, he's also had the benefit of protection, or favouritism—Prost with then-FIA President Jean-Marie Balestre and, if you believe Webber (and that's not to suggest the Australian is wrong, or foolish), Vettel within the Red Bull camp.
Of course, Prost's mistake, for want of a better word, was for daring to beat or cheat Ayrton Senna, the Brazilian every inch a People's Champion. Did events in '89 (and in '90, when they went in Senna's favour), affect his standing in the eyes of some fans? Yes. Should it? Almost certainly not.
Prost retired in '93 a four-time world champion; Schumacher's first retirement (and second) saw him bow out seven times a title winner. That's their motorsport legacy, not the controversies.
That's also what the sport needs to acknowledge about Vettel in the modern day. You might think there's little ground in this argument. After all, Vettel was not booed. Not obviously, anyway.
But the crux of this issue is that he was perceived to have been, and the reason is because he has been in the very recent past.
The bottom line is he may well have been booed but it is that perception which is a shame for the sport. Vettel's popularity is a major talking point, it has to be, because as world champion he is the global face of F1.
It's far from encouraging to see the sport assume its poster boy, a deserved world champion who had just won a Grand Prix (a heinous crime), was the subject of post-race criticism than the political actions of a renowned environmental protest group.