Spaniard Alejandro Valverde crossed the line second today to retain the lead with just one stage to go.

It came in an undulating 189.7 kilometres route from Tortosa which included a category one climb 35km from the finish.

However, dramatic scenes unfolded earlier as a technical descent 29km split the peloton. 

Valverde, Alberto Contador and other overall contenders survived, but Froome and many of his Team Sky team-mates were cut adrift and unable to close the gap. 

Multiple attacks were launched from the leading group as the finish line neared. 

Two Italian riders in Astana's Dario Cataldo and BMC Racing Team's Alessandro De Marchi briefly broke clear with 10km to go, but were swiftly hauled in as a sprint finish unfolded.

Orica-Scott's Impey timed his effort superbly to break clear and win in 4 hours 34min 14sec. 

Valverde crossed in second in the same time as FDJ's Frenchman Arthur Vichot took third. 

Valverde now leads a Spanish 1-2-3 in the overall stakes.

‎Trek–Segafredo's Contador lies 53sec behind with Valverde's Movistar team-mate Marc Soler third.

Froome, who had held second place at the beginning of the day, tumbled out of contention after his group eventually crossed 26:36 behind.

A final 138km stage will take place in Barcelona tomorrow.