Geraint Thomas is set to win the Tour de France on Sunday after protecting his yellow jersey on the stage 20 time trial from Saint-Pee-sur-Nivelle to Espelette.

Thomas will become the third British winner of the race, joining Sir Bradley Wiggins and Chris Froome, with the trio winning six of the last seven editions, all in Team Sky colours.

His closest rival at the start of the day, Tom Dumoulin, won the penultimate stage by one second from Chris Froome, but with Thomas only 14 seconds back the Welshman had more than enough in hand.

Thomas will carry a lead of one minute and 51 seconds into Sunday’s traditional procession into Paris before the sprinters fight it out for glory on the Champs-Elysees.

Thomas was embraced by his wife Sara and Team Sky principal Sir Dave Brailsford at the finish, and wiped away a tear.

“I can’t believe it,” Thomas said. “I’m welling up. I don’t know what to say. It is just overwhelming. I didn’t think about it all race and suddenly I won the Tour.”

Speaking of Saturday’s stage, he said: “I felt good, I felt strong, I felt really good actually. I was maybe pushing a bit hard sometimes.

“Nico (sports director Nicolas Portal) told me to just relax, take it easy and just make sure I win the tour, and that’s what I sort of did.

“It’s just overwhelming. I can’t speak man. It’s just incredible. I believed I could beat the guys here but to do it on the biggest stage of all over three weeks, it’s insane.

“The last time I cried was when I got married and I don’t know what’s happened to me.”

Froome, who came here looking for a record-equalling fifth Tour title and seeking a rare Giro-Tour double, had to settle for third place overall, taking back the final podium spot from LottoNL-Jumbo’s Primoz Roglic with his second place on the day.

Though it is not what he set out for, Froome said he was happy after 13 months which have seen him win all three Grand Tours on the bounce but also face a nine-month battle to clear his name after returning a test with high levels of salbutamol at La Vuelta last year. He was cleared on the eve of the Tour.

“I’ve had a difficult year,” Froome said. “I didn’t think it was possible to get on the podium so I’ve very happy about that.”

Brailsford added on Eurosport: “To have a little bit of support in helping people achieve their dreams is why we do it really. It’s a very powerful and very rewarding thing to be involved in. Chris has achieved many, many of his dreams and to see Geraint achieve his on this time, this particular race, is quite moving.”

There was brief confusion when the timing splits appeared to show Froome had beaten Dumoulin by one second to take the stage, though it was soon corrected.

“That’s crazy,” Dumoulin said. “I didn’t know anything about split times and I still thought Froome was one second ahead of me when I crossed the line. Wow.”

Thomas emulates Wiggins in converting himself from an Olympic team pursuit champion into the winner of the world’s biggest road race.

The 32-year-old had never before finished in the top 10 of a Grand Tour. In his only previous serious attempt to win one, he was forced to withdraw following a crash midway through last year’s Giro d’Italia.

Intermittent rain, the first significant downfall of the entire Tour, created unpredictable conditions on Saturday’s 31-kilometre course.

There was one significant scare for Thomas with around 19km to go when the bike almost slipped from underneath him on a right-hand bend.

Thomas may have known he had a buffer to play with, but he was not taking it easy as he was fastest through the first and second splits before grinding up the Col de Pinodieta and dropping back.

Dumoulin had to console himself with his third career Tour stage win – all of which have come in individual time trials.

The Team Sunweb rider’s day did not get off to an ideal start when he could not find his time trial skinsuit in the morning.

But with his clothing sponsor based just across the Spanish border in San Sebastian, an emergency call was placed and they whipped him up a new set of the world champion’s rainbow stripes in time.

Irishman Dan Martin shipped more than two minutes in the time trial, but the UAE Team Emirates rider – named the most combative in the Tour overall – did enough to protect his top 10 place as he is set to finish eighth overall.