Dumoulin revealed he was on edge for most of the day after he couldn't find his world championship time trial skinsuit, specially designed for the Dutchman to reduce aerodynamic drag. Between them they have taken six titles in the last seven years.
Quintana's win lifted him from eighth overall at 4m 23s, to fifth at 3m 30s to Thomas, whose lead on a reshuffled top order rose as a result of Froome's eighth-place finish at 1m 35s to Quintana.
Asked what advice he would give Thomas, Froome replied laughing: "I don't think he needs any".
Convoy: Chris Froome, right, and Geraint Thomas, wearing the overall leader's yellow jersey, climb Col du Portet pass. The Briton vowed "I wont take my eyes off the ball".
How Geraint Thomas all but sealed his historic Tour de France victory
Team Sky's performance manager Rod Ellingworth, who has worked with Thomas since he was a teenager, said: "He's often been committed to someone else in the team and he never falters in that". "I'm surprising myself on this Tour but we're not in Paris yet". It has been a rollercoaster of emotions for me and the whole family at home.
On the road Thomas has mirrored the path of Froome, who worked for the team to secure Wiggins his title before moving on to win the race himself with Thomas as his assistant.
American rider Lawson Craddock, who broke his shoulder in the opening stage and sits last overall, also broke down into tears upon reaching the finish.
But Thomas was not looking beyond his next pedal stroke. "I think he's doing just fine". "I am not thinking about the end game".
"I first heard that I was second by one second but it's the other way round and it's insane", said Dumoulin, who suffered a mishap when he lost his aerodynamic skinsuit. This Tour is spread out, but it comes down to [Sunday]. "I've won the Tour, man!" "What will be, will be". "But it's fantastic to finish the Tour this way and make the final podium for the first time".
Thomas still had the air of a Tour winner-in-waiting. That was also the case in stages 16 and 17 in the Pyrenees on Tuesday and Wednesday and in the Alps, where the Tour spent three days and he claimed back-to-back victories on stages 11 and 12. "But he rode away from us on a straight stretch and I was fully sprinting and couldn't get one metre closer".
- Samsung Display's 'Unbreakable' Display Certified in US | Be Korea-savvy
- U.S. economy posts best performance since late 2014
- No regrets for McIlroy after Open second
- United States suggests hosting new Trump-Putin meeting in Washington in late 2018
- Israel sounds sirens, fires interceptor missiles on Syria frontier
- What is the Fortnite Android Release Date?
- $10,000 lottery tickets sold at neighboring Broad Street businesses
- Total Eclipse of the Moon on 27 July 2018
- Water is buried beneath Martian landscape, study says
- Barnier blows fresh hole in May's Brexit proposals over Border