London - Julian Alaphilippe leads the Tour of Britain heading into the penultimate stage as the French rider finished second behind stage six winner Wout Poels on Friday.
Alaphilippe, of the Quick-Step team, finished two seconds behind Team Sky's Poels on the 168.3km ride from Barrow-in-Furness to Whinlatter Pass.
Britain's Hugh Carthy, of the EF Education First-Drapac, team was 12 seconds behind Dutchman Poels in third.
Poels and Frenchman Alaphilippe, who won the King of the Mountains' polka dot jersey at the Tour de France last July, pulled away on the final climb up Whinlatter.
With two stages remaining, the 26-year-old Alaphilippe leads Poels by 17 seconds in the general classification.
"Second is really nice, it's going to be a hard fight - no more uphill finishes, everything is flat. But we'll keep on trying," said Poels, a team-mate of Tour de France winner Geraint Thomas.
"I'm really happy - the team did a really good job - G (Thomas), Ian Stannard - so it's really nice that I could finish it off," he said.
Slovenian Primoz Roglic, the overnight leader, saw his chances of overall victory dented when he dropped to third place, a further 15 seconds back.
Alaphilippe becomes the fifth Tour of Britain leader in six days of racing after also winning stage three in Bristol.
"All of my guys did an incredible performance and everybody was riding for me today to protect me before the last climb," Alaphilippe said.
"Roglic was on my wheel at the end and I tried to attack the last time to drop him. I'm really happy to take the (leader's) green jersey."
Saturday's penultimate stage runs from West Bridgford to Mansfield before the climax to the race in London on Sunday.
Leading positions after stage 6:
1. Wout Poels (NED/Sky) 4hrs 1min 51 secs, 2. Julian Alaphilippe (FRA/QST) at 2 secs, 3. Hugh Carthy (GBR/EFD) at 12 secs, 4. Jonathan Hivert (FRA/DEN) at 21 secs, 5. Patrick Bevin (NZL/BMC) at same time
Leading general classification after stage 6:
1. Julian Alaphilippe (FRA/Quick-Step) 19hrs 46 min 54 secs, 2. Wout Poels (NED/Sky) at 17secs, 3. Primoz Roglic (SLO/LNL) at 32 secs, 4. Patrick Bevin (NZL/BMC) at 46 secs, 5. Bob Jungels (LUX/QST) at 51 secs