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Roglič and Bernal went toe-to-toe atop the Grand Colombier in an epic duel with around 300m to go, the Slovenian edging INEOS leader moments later to cross the line four seconds ahead.
Jumbo-Visma's strength was again evident as they hit the slopes of the final 17km ascent with the full Roglič, Tom Dumoulin, Steven Kruijswijk trident, and Kiwi George Bennett for good measure.
The yellow army were there for most of the climb, Kruijswijk until the final kilometre before Roglič branched out on his own.
“Today was a tough day," Roglič said after the 144km stage from Saint-Vulbas. "Because of the high pace and the long climbs.
But the whole team once again did a fantastic job and showed how strong we are. I’m glad I was able to finish it off again. We are positively surprised by how strong we already are as a team."
"You never know exactly where you stand after such a long break. As far as we can see now, we have already shown that we are at a reasonably high level. At the same time, this is only the first race in a long time, so we should certainly continue to do our best in this way. The results will then come naturally.”
Meanwhile, Geraint Thomas bowed out after ably guiding the INEOS train to the foot of the Colombier, handing over the reins to Andrey Amador then Chris Froome.
Then it was up to Jonathan Castroviejo, who drove the bunch hard but Bernal found himself isolated in the final kilometres against four Jumbo-Visma riders.
But Bernal didn't sound worried as he spoke to reporters following the stage.
"Today we showed that we're here to ride a very fast pace as well," he said. "We did our race and we should he happy with how it went, not just here but in La Route d'Occitanie.
"Our big goal is the Tour. This is a race to prepare for the Tour. Some other big riders from other teams were also dropped early today. That doesn't mean that they won't be up there in the GC at the Tour de France." "We need to be calm and to know that we're just here to train."
"For sure we want to do good training but they will be there at the Tour de France."
While Tasmanian Richie Porte found himself well down the overall classification before the final stage, on the Grand Colombier he sparked several attacks in the final three kilometres to cross the line fifth, continuing the form that netted him second place behind an in-form Vlasov at hte Mont Ventoux.
We won't have to wait until the Tour de France to watch INEOS and Jumbo-Visma to suit up again for another fight -they both have juicy line-ups for the Criterium du Dauphine - LIVE and FREE on SBS Viceland from Wednesday 12 August - Sunday 15 August.
Team INEOS to the Criteriuem du Dauphine: Froome, Bernal, Thomas, Castroviejo, Michal Kwiatkowski, Pavel Sivakov, Dylan Van Baarle.
Jumbo-Visma at the Criterium du Dauphine: Roglič, Dumoulin, Kruijswijk, Robert Gesink, Sepp Kuss, Tony Martin, Wout van Aert.