Leading until the final 100m, Alberto Contador (Saxo Bank) seemed to have the mountain top finish in the bag before being jumped by Valverde (Movistar) and Rodriguez (Katusha) just before the line.
Chris Froome (Sky) had to settle for fourth position, 15 seconds down on the stage winner who remains in the leader's red jersey with a 33 second advantage over his Sky rival.
Stage eight saw the peloton travel from the Spanish town of Llieda over the border into Andorra and up to the Pyreneean mountain top finish at Collada de la Gallina. The route gradually rose into the mountains before climbing the category two ascent of the Alto de la Comella 20km from the finish line before a technical descent to the foot of the punishing Collada de la Gallina, on which the stage was decided.
From the off, attacks were constant but with an average speed of 52.6km/h for the first hour of racing, it's not surprising that nothing stuck. When a break did eventually get away just before the 100km mark it consisted of Cameron Meyer (Green Edge), Javier Ramirez (Anadalucia), Amaël Moinard (BMC), Mickaël Buffaz (Cofidis), Javier Aramendia (Caja Rural) and Martijn Keizer (Vacansoleil).
This group were allowed to forge ahead and at one point had a lead of over nine and a half minutes. The six riders contested both of the intermediate sprints from which Buffaz took maximum points. He was followed across the line by Keizer in second and Aramendia in the first sprint at La Seu d'Urgell and by Meyer in second and Ramirez in third at Andorra la Vella.
But while this group battled it out for sprint points, behind them Sky had taken control and from a nine minute gap at 45km to go, the lead was whittled down to just five and a half minutes as the two climbs of the day approached.
On the climb of the Alto de la Comella, Sky drove hard and fast on the front and it seemed that the other favourites were happy to let them continue to do the work. Up front the six breakaway riders became four as Keizer and Aramendia dropped off, but the gap continued to tumble and following the descent of the category two climb, there was under two minutes between the leaders and the chasing pack.
The Collada de la Gallina, a category one climb of 7.5km with ramps of between 15 and 21% was made for a showdown between the favourites and that is exactly what we got. Four kilometres from the top and the escapees began to attack each other. Cameron Meyer came out on top and was free to take a solo run for home.
With only 45 seconds of an advantage, he never looked like he would make it the whole way and was indeed passed by the leaders inside the last two kilometers. He battled hard to eventually finish just 1: 51 down at the finish line but the real race had passed him out.
With just three kilometres remaining, Valverde attacked for home. Fellow Spaniard Javier Ramirez, who was fading from the breakaway, provided a brief tow as Valverde seemed to be opening a gap on his rivals, but no sooner had he attempted to get away, as he was reeled back in by Froome, Rodriguez, Daniel Moreno (Katusha) and Contador.
The race was now down to five riders and as Froome and Rodriguez attacked on after another, Contador seemed content to follow. Inside the final kilometre and the Sky man gave it one final dig, sprinting to try and shake off the others, but without any success.
It was here that Contador went for home. The Spaniard dug deep and with gritted teeth seemed to have victory sewn up. As he passed the 250m, 200m, and then 150m mark he seemed home and dry. And then, just as he turned the final bend, as if resurrected from the dead, Valverde appeared with Rodriguez in his wheel.
The pair stole the march on Contador and not only did he not win the stage, but he lost out on the time bonuses that would have made such a difference to his challenge for the overall victory.
In the end it was a brave effort from Sky, but Froome didn't seem to have the legs or the tactical mind to outfox Contador, while El Pistolero himself was out done by the guts and determination of Valverde and Rodriguez.