Hotly-tipped Tour de France contender Primoz Roglic won Tuesday's stage four on the race's first summit finish but failed to drop any of his key rivals in the process, including overall leader Julian Alaphilippe.
On a perfect day for racing the Vuelta a Espana champion edged home his Slovenian compatriot Tadej Pogacar in second, while Guillaume Martin was third after 160.5km rolling run to the 1850m altitude finish line.
The Alpine summit stage was billed as the moment the true form of the various contenders would be revealed on the 7.1km climb to the ski resort of Orcieres-Merlette at a 6.7% average incline.