Croix-de-Chauboure - Sky rider Richie Porte of Australia haswon the 204km fourth stage of the Paris-Nice "Race to the Sun" on Thursday, edging out Welsh team-mate Geraint Thomas on the run-in at Croix-de-Chaubouret.
World champion Michal Kwiatkowski of Poland regained the overall leader's yellow jersey he relinquished only 24 hours earlier to Australian's Michael Matthews.
Porte, the winner in 2013, and Thomas broke away over the final kilometre of the uphill finish and crossed the line, at an altitude of 1,201 metres, a full eight seconds clear of Kwiatkowski and Danish rider Jakob Fuglsang.
In the overall standings, Kwiatkowski leads Porte by just a second with Thomas also breathing down his neck, just two seconds further back.
On Friday, the fifth stage takes the riders on a 192.5km ride from Saint-Etienne to Rasteau, on a day when there are few hill climbs to negotiate.
Results on Thursday in the fourth strage of the Paris-Nice cycle
race, the 204km from Varennes-sur-Allier to Croix-de-Chaubouret:
Richie Porte (AUS/SKY)5hr 18min 39sec, 2. Geraint Thomas (GBR/SKY) same
time, 3. Michal Kwiatkowski (POL/ETI) at 8sec, 4. Jakob Fuglsang
(DEN/AST) 08, 5. Tejay Van Garderen (USA/BMC) 17, 6. Rui Costa (POR/LAM)
24, 7. Tony Gallopin (FRA/LOT) 24, 8. Fabio Aru (ITA/AST) 24, 9. Rafael
Valls (ESP/LAM) 24, 10. Simon Spilak (SLO/KAT) 24