Tour de France: Dessel takes yellow jersey on first Tour but true leader remains up in the air

The pack heads into the Pyrenees for stage 10

If anybody expected anything remotely like an answer in the Tour's first mountain stage as to who would inherit the throne left vacant by the seven-times overall winner Lance Armstrong, they were to be sadly disappointed.

Instead, as the Tour's theoretical major favourites all kept their powder dry in the damp, swirling mist that enshrouded the race on its 190.5km trek through the Pyrenees, two virtually unknown riders - the Spaniard Juan Miguel Mercado and the Frenchman Cyril Dessel - stole the show.

The two survivors from an early break of 13, Mercado and Dessel rode into the elegant finish town of Pau over seven minutes ahead of the main pack.

In the final two-man sprint, Mercado outgunned the Frenchman to take the second Tour stage of his career, while Dessel settled for the equally prestigious prize of the yellow jersey and the lead in the King of the Mountains competition.

Agreements between two riders who both have something to gain from a joint move are not uncommon, but not so on this occasion.

"Mercado's already got one stage win, so I wanted to go for it." Dessel - riding in his first Tour following a last-minute exclusion from his previous team's line-up - pointed out.

"But in any case, taking the yellow jersey is something I could hardly have expected in my first ever Tour, and I'll settle for that." For Mercado the victory was equally satisfying, given that his team - Agritubel - was the only one to be invited to the Tour, rather than gaining automatic entry through the ProTour league.

Mercado recognised that he had never expected such a prestigious win so early in the Tour.

"I'd had a rough spring, but gradually my form improved." Mercado said afterwards. "I never suspected, though, I could get through a break of 160 kilometres. Really, Dessel and I both knew that by collaborating we had a lot more to gain than to lose."

Dessel's advantage overall is now 2min 34sec on Mercado, with former leader Serhiy Honchar in third in 3:45 - a bizarre development for a race used to seeing Lance Armstrong destroy the opposition the moment the Tour entered the mountains.

Instead, the main group of favourites trundled over the two major climbs of the day, the Soudet and the Marie-Blanque, with no signs of any real attacks.

For T-Mobile, the team who had four riders, including Honchar, in the top five yesterday morning, this passivity can only be due to a calculated gamble - that Dessel will soon crack.

Shorn of their major leader, Jan Ullrich, after his implication in a doping scandal, with so many riders high up on classification there had been speculation that a power struggle could take place inside the magenta-coloured squad.

But instead T-Mobile appear to be placing all their bets on the German Andreas Klöden, second in the 2004 Tour.

This is logical enough: Honchar's limitations in the mountains became clear as he was all but dropped from the main group of chasers yesterday and Klöden is the only rider left in the race to have finished on a Tour podium before.

If the issue of who the most powerful Tour squad have made their leader post-Ullrich was resolved on stage 10, the battle for the overall lead was, disappointingly, postponed.

But such a delay can by no means be indefinite: today's first mountain top finish, on the Pla de Beret in Spain, should finally see the riddle of the 2006 Tour winner begin to be resolved.

Alasdair Fotheringham writes for Cycling Weekly