If Chris Froome holds onto the Tour de France yellow jersey all the way to Paris, he will have Geraint Thomas to thank for yet another outstanding ride in support of his leader.

After finishing a third day in the Pyrenees, where Thomas now sits fifth overall, Froome called Thomas’s ride “fantastic” — and suggested the Welshman could yet make the podium of this year’s race.

Thomas took over from Richie Porte with five kilometres left under the driving rain to Plateau de Beille. He motored on the front and kept his leader protected while Movistar’s Nairo Quintana and Alejandro Valverde, and Tinkoff-Saxo’s Alberto Contador attacked.

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The ride was reminiscent of Froome himself in 2012, when he supported Bradley Wiggins through the mountains and to overall victory in the Tour de France.

“It’s a role I’m familiar with, a role I’ve done in the past,” said Froome. “G’s been absolutely great and fantastic, in the cobbles, the cross-winds and rain in the first week. He’s finished the hardest Pyrenean stages now, and he’s been right up there in both of them.”

Thomas sits 4-03 minutes back in the overall, but the feeling is that if he keeps riding like he has so far, then he could even help Sky to a one-two finish in Paris – just as Froome managed behind Wiggins in 2012.

“Of course, the team is focused on trying to keep yellow, that’s the first goal,” said Froome, “but I definitely think G is capable of [placing second]. He’s fifth at the moment, and there’s not much between fifth and second, really. Anything’s possible. If he continues on riding like he is, he should be right up there.”

Thomas has raced grand tours before as a helper, but never at this level. He attributes the step up to his decision to turn his back on the track.

The results came almost immediately. This year, he won the Volta ao Algarve, rode solo for the E3 Harelbeke title and placed second overall in the Tour de Suisse. Now he is performing in the biggest race of all.

Joaquin Rodriguez takes the stage win after a gruelling day in difficult conditions (Watson)

Thanks to his ride up the 15.8-kilometre climb today, Froome was able to keep his rivals under control and even launch a small attack of his own. He closed 6-47 behind stage winner Joaquím Rodríguez (Katusha), but alongside his overall rivals. Thomas was also there in the elite group of nine.

“I think he’s been progressing for the last three years and he’s done an exceptional job over the last week,” Sports Director Nicolas Portal said.

“He is missing the punch but he can ride for a long time at a high speed. He was born on the track, but he has the genetic capacity to maintain a high speed in the mountains.”

If Thomas can protect Froome as Froome did for Wiggins in 2012, then the next logical step appears to be Thomas leading a grand tour team himself — and Sky acknowledge that that day is not far off.

“I think [a podium place this year] is possible,” continued Portal. “It’s not the objective, but I think it’s possible.

“Winning a grand tour is something else. Being there and being able to help in the final is already a big, big thing, a real quality. After that, winning is something else. There are only really three or four riders at the moment who can do that.”

“G’s got a really bright future ahead of him in terms of grand tour riding,” Froome added.

“I don’t think it’s going to be long until we see him take leadership for himself in a grand tour. He definitely deserves it.”

The Tour faces mid-mountain stages over the next two days, but afterwards it heads into the Alps. Thomas will be able to try for a podium while helping Froome, and in the process show just how far he can go in grand tour racing.