Fayence - Briton Simon Yates came home alone in Friday's sixth stage of the Paris-Nice with France's Julian Alaphilippe retaining the leader's yellow jersey.
Orica rider Yates crossed the line 17 seconds up on Colombian Sergio Henao who gained a dozen seconds on fourth-placed Alaphilippe.
Alaphilippe heads the general classification from his compatriot Tony Gallopin, over half a minute adrift, with Henao 46 seconds away in third.
Yates made a decisive move on the penultimate climb 20km from the finish of the near 200km ride between Aubagne and Fayence.
The 24-year-old brother of last year's Tour de France fourth Adam Yates moves up to eighth overall at 1:37.
"There's still a lot of time to take away from Julian Alaphilippe but he's such a phenomenal rider. He's one of the best riders of our generation," said Yates.
Alaphilippe lost time when unable to stay with Henao when the South American reeled in a breakaway from Australian Richie Porte.
"It was hard, I had cramp at the foot of the climb," the Frenchman revealed.
"He (Henao) is going to be a serious rival tomorrow."
Saturday's 177km seventh and penultimate stage concludes with a 15.7km climb up to the 1 678m col de la Couillole, the highest finish in the race's 75-year history.
"A rider like Henao can build up gaps on a long climb like that, but he's not the only one, I have out watch out for others too," observed Alaphilippe.
Results of the Paris-Nice sixth stage, a 193.5km ride from Aubagne to Fayence on Friday:
Simon Yates (GBR/Orica) 4hr 37min 51sec, 2. Sergio Henao (COL/SKY) at
17sec, 3. Richie Porte (AUS/BMC) 26, 4. Julian Alaphilippe (FRA/QST) 29,
5. Dan Martin (IRL/QST) 29, 6. Ion Izagirre (ESP/BAH) 32, 7. Jakob
Fuglsang (DEN/AST) 32, 8. Alberto Contador (ESP/TRE) 32, 9. Ilnur
Zakarin (RUS/KAT) 32, 10. Tony Gallopin (FRA/LOT) 32.
Julian Alaphilippe (FRA/QST) 21hr 58min 22sec, 2. Tony Gallopin
(FRA/LOT) at 0:36, 3. Sergio Henao (COL/SKY) 0:46, 4. Gorka Izagirre
(ESP/MOV) 0:57, 5. Daniel Martin (IRL/QST) 1:20, 6. Ilnur Zakarin
(RUS/KAT) 1:31, 7. Alberto Contador (ESP/TRE) 1:34, 8. Simon Yates
(GBR/ORI) 1:37, 9. Ion Izagirre (ESP/BAH) 2:04, 10. Warren Barguil
(FRA/SUN) 3:08, 11. Philippe Gilbert (BEL/QST) 6:41, 12. Rudy Molard
(FRA/FDJ) 7:25, 13. Romain Hardy (FRA/FVC) 9:59, 14. Bram Tankink
(NED/LNL) 14:50, 15. Richie Porte (AUS/BMC) 15:54.