Ralf's rating is higher than big brother's

Most crucially of all, after Silverstone, F1 begins a six-week period during which no testing is permitted. The ban means those cars currently suffering problems - such as Ferrari are having with their Bridgestone tyres - will have little chance of finding a solution. Hence the momentum stays with the car that is currently dominant, meaning Williams, and specifically Ralf.

"I said at the beginning of the season that Michael would win it, but now you've got to wonder about Ralf,'' said British ex-F1 driver Mark Blundell.

So, weeks after questions were asked yet again about the unfathomable mindset between Venus and Serena Williams, the same debate is looming over F1. Until now, anyone unaware of which of the two brothers is the elder would have had no trouble working it out. The controversy over Ralf 's apparent reluctance to challenge Michael for the lead last month in Canada epitomised Ralf 's deference to his sibling.

"There is a lot of big brother, little brother stuff going on there,'' said Brundle. "Overtaking isn't Ralf 's strong suit and it's usually Michael he needs to overtake. Ralf 's difficulty with that damages him a lot. Two years ago, when Michael stuck Ralf in the pit wall at the Nurburgring, he nailed him right up against the wall with no quarter-given. Ralf would never do that in return. They have different standards of what's right and wrong.

"Ralf is so hard to understand as a driver. He blows so hot and cold. He can figuratively go to sleep halfway through a race and fall off the circuit. Then, all of a sudden, he's turning into an unbeatable machine.''

An interesting window on the competitive dynamic between the brothers is revealed in Michael's new authorised biography. Intriguingly, in a book which sets out to flesh out Michael as a caring family man, Ralf is barely mentioned.

Similarly, he recently listed the "great talents'' in F1 as Raikkonen and Fernando Alonso. No mention of Ralf. He has broadly maintained the brothers' policy of being positive about each other, but at Magny-Cours he put Ralf 's form down to his car, not the driver.

"Ralf 's current form is nice, but not sensational,'' said Michael. "He has always been fast and now he has the car to show it. I'm very happy for Ralf. He is absolutely in among the championship contenders. Ferrari need to be concerned about Williams. We must get our act together. We have to improve.''

Away from the track the two are not especially close. Michael lives in Switzerland with his wife and two infant children, while Ralf prefers Monaco for his wife and young son.

Ralf is not universally popular in the paddock and is commonly described as being just like Michael but without the charm. Ho ho. At the very least he has a tendency to feel generally hard done by.

"If things aren't going well I get a lot of stick,'' Ralf said recently. "When they do go well everyone is happy. I'm used to it by now.'' The idea that such a pattern is as it should be did not seem to occur to him. Above all things, however, he loathes the incessant questions about his brother.

"I just cannot understand the constant comparisons with Michael,'' he insisted last weekend.

Michael has no such difficulty. Asked in France who is currently the best Schumacher in F1, he faced facts.

"At the moment,'' he said without hesitation, "it is Ralf.''