The script had been written for Team Sky's Bradley Wiggins to take the overall lead in the Vuelta after the time trial on Stage 10, but his team-mate Chris Froome surprised everyone, writes Matt Rendell

Chris Froome’s career so far has not been gone according to the usual scripts. He was already a promising young rider when he learned, in adolescence, that the champions of each cycling country get to wear a special jersey made up in their national colours. Precocious, he telephoned the Kenyan national cycling authorities.

"When are the Kenyan championships?"
"There aren't any."
"How do I get to wear the national champion's jersey?"
The question was greeted with a laugh.
"I tell you what, if you design the jersey, and then sew it together yourself, you can be the national champion."

He did.

On Monday in Salamanca Chris Froome wore another special jersey: the red one that distinguished the leader of the Vuelta a Espana. His race leadership is as deserved as it is unexpected: for nine days he has played the part of the perfect domestique for Bradley Wiggins, the undisputed leader of a Sky team that looked decidedly second-string pre-race, with no Edvald Boasson Hagen, no Rigoberto Uran, no Geraint Thomas.

Step up Chris Froome. In the first eight stages he finished in the same group as, and in the same time as, his leader. In stage nine, he led Wiggins towards the Covatilla ski station above the town of Bejar, and then, as the rode turned and a dangerous cross-tailwind began to buffet the riders, he forged ahead with Wiggins on his wheel, shedding contenders and specialist climbers as he went.

Then, when he was spent and Wiggins took the lead, he managed to hang on and finish just three seconds behind his leader. After such an outstanding ride, we wondered if he might sit up and take today easy. He didn’t.

It was a tale of two time trials. The favourites before the stage – all but Wiggins – set off early. Taylor Phinney (BMC Racing Team) set the early time to beat. Fabian Cancellara (Leopard-Trek) beat it by a handful of seconds. Then Tony Martin of HTC-Highroad beat Cancellara's time by a couple of minutes. Martin's time looked safe as several hours, and several dozen riders passed.

Then Wiggins passed the first intermediate split after 13.3km a second faster than Martin had – and, incidentally, 24" faster than his team-mate Froome. Wiggins was not just humbling the other GC contenders; he was challenging the time-trial specialists who had no interest in the race overall.

Streamlined and purposeful, he sped towards the second split at 30km. But something had gone wrong. He was now 19" behind Martin’s schedule. Still, perhaps Martin, who has the beating of Cancellara in the grand tour time trials – how will they compare in the Worlds ten days after the Vuelta finishes? - had accelerated. But Wiggins had lost 23" with respect to Froome, too. And it would only get worse.

Eight seconds – again.

Over the final 17km, his deficit to Martin grew by another 1'03", and to Froome, by another 33". Let’s keep things in proportion. Martin rode with characteristic brilliance to win the stage. Wiggins conceded 1'22" to him, but Wiggins beat Cancellara by five seconds. On any other day in a career, it would be a day of celebration. But Froome beat Wiggins by 23". For that reason alone, Wiggins’ ride looks lustreless.

Jakob Fuglsang (Leopard-Trek) took advantage of Wiggins’ slightly under-par finish to retain eight seconds of his overnight 23" advantage over the Londoner. The Dane was sixth in the stage, six seconds slower than the youngster, Phinney. Maxime Monfort, 10th at 2m 06, and Fredrik Kessiakoff, 11th at 2m 18, rode well to maintain their positions in the top six of GC, while the overnight race leader Bauke Mollema rode muscularly but gracelessly and slumped to 25th at 3'09" for the stage, and to seventh in GC at 1'07".

The day we expected ended with Wiggins leading GC by a substantial margin. Instead, Froome wrote his own script. I only hope it will be as big a story in the sports pages as a win by Wiggins would have been.

So: Froome leads, with Fuglsang second eight seconds back, Wiggins third at 20", followed by Vincenzo Nibali (31"), Fredrik Kessiakoff (34"), Maxime Monfort (59"), then Juan Jose Cobo, who over-performed to sit 8th at 1'47", Radio Shack's Janez Brajkovic who under-performed and stands ninth at 2'04", and then his team-mate Haimar Zubeldia in 10th overall.

Sky riders first and third, Leopards second and sixth, Geox’s eighth (Cobo) and 13th (Menchov), and the two Radio Shacks at ninth and 10th. All of them scrunched up together in less than two and a half minutes.

"Froome ... can expect a return to servitude as the peloton heads to the Cantabrian mountains and Wiggins's quest to become the first Briton to win a grand tour continues." So sayeth Tuesday's Guardian, no doubt capturing the intuitions of many.

But cycling isn't that simple. Remember Cordoba? A dominant Liquigas-Cannondale team, riding four against one, couldn't even ensure its leader got the eight second bonus for third place. How much more difficult is it to take two riders in your team and swap their position in GC? Can't be done.

In any case, look again at GC: Sky, Leopard-Trek, Radio Shack and Geox have options. Ten stages in, it comes down to this: Froome and Wiggins against Fuglsang and Monfort against Brajikovic and Zubeldia against Cobo and Menchov.  And look at the final week of the race, when it enters the Basque Country.

The abrupt climbs and sea breezes coming off the Bay of Biscay could split the peloton and favour breakaways. Covering them could be hellishly difficult, especially for the three isolated contenders in the top 10: reigning champion Nibali, the surprise of the Vuelta so far (alongside Froome), Kessiakof, and Rabobank leader Mollema.

I suggest that between now and the next rest day on Monday 5 September, all four teams will aim to keep their twin leaders well-placed, if they have the legs, before the onslaught of Joaquin Rodriguez,  Mikel Nieve and – why not? – Dan Martin. But, for all the circus climbs and fancy uphill finishes, I suspect the Basque Country could hold the key. And there, you're going to want two GC men.

So forget all your thoughts of undisputed leaders and faithful domestiques. At this stage of the race, things are much more complicated – and much more interesting!

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