THE sight of spectators parting like the Red Sea in front of Tour de France riders as they go over the crest of a mountain is unique in world sport.

But what used to be an ego-boosting guard of honour for champions of the past has turned sinister in 2015.

The continued spectre of doping allegations looms large over cycling's blue riband event.

It is to such an extent that race leader Chris Froome has had a bag of urine thrown at him and his second lieutenant at Team Sky, Australian Richie Porte, has been punched by a member of the crowd.

With that in mind, Froome and his team-mates must now view the looming sight of their mountain-top welcoming party with a sinking feeling shared by those preparing for the Pamplona bull run.

Tour de France fans, who have been known in the past to let enthusiasm get the better of them, are desperately looking for someone to take out their lingering frustrations on following the Lance Arsmstrong saga, and it looks like Froome is public enemy number one.

There is no evidence to suggest he has done anything wrong, only maybe that he is too good for his own good.

So while heroes of yesteryear would quite often have to bat off fans who had maybe let the moment, or a bottle or two of the region’s finest, get the better of them, Froome et al must ready themselves for physical and verbal abuse.

They have battled on regardless and the Kenyan-born Brit is now just three stages away from claiming a second yellow jersey.

But that jersey is tainted.

While Armstrong used to be praised for his metronomic ability to withstand all the challenges his rivals threw at him, Froome has raised doubts by displaying similar qualities.

His ability to pounce on every attack and pick a stage to blow the field apart just doesn’t wash with the Tour-loving public.

The fact he is set to become the Tour’s third British winner in four years, following on from Sir Bradley Wiggins’ victory in 2012 and his own 12 months later, may have something to do with the angry response from the French locals.

But the reaction to Team Sky’s dominance goes beyond any anti-British sentiment.

Froome has even had to defend himself against assertions from an “eminent doctor” that the power he used to pedal away from his rivals to win stage 10 was “not physiologically possible”.

The British champion-in-waiting retorted with a Gallic shrug of his shoulders – he has conformed with every dope testing regulation and continues to come up clean.

Short of handing over his entire training data to the powers-that-be, effectively giving away the secret of his success to rivals, there is nothing more he can do.

And that is Armstrong’s ultimate legacy.

The American, and his doping predecessors, have shaken the faith of fans in what remains one of the world’s ultimate sporting challenges.

Mere mortals watch these guys in awe as they sprint up one-in-10 gradients, but while fans of the past would scratch their heads in amazement, now they clench their fists in anger.

Sadly, for now at least, that is something Froome and his fellow racers will have to learn to live with.