Haytor - Steve Cummings put himself in pole position to emulate Bradley Wiggins in 2013 and become only the second British rider to win the Tour of Britain after taking the overall lead on Friday.
The 35-year-old is enjoying an Indian Summer in terms of his career with stage wins this year on four major races including the Criterium du Dauphine and the Tour de France.
And he now holds a 49-second lead over Dutchman Tom Dumoulin after Friday's challenging sixth stage from Sidmouth to Haytor on Dartmoor.
Overnight leader Julien Vermote of Belgium - who had led since winning Monday's second stage - had an awful day in the saddle and slipped out of the top 10 in the overall standings.
The stage itself went to Dutch rider Wout Poels, the Team Sky rider going clear in the final 1.5km to record his third win on British roads.
Cummings - second in the 2008 and 2011 editions - came eighth.
Saturday's stage is a time-trial which could be a cliffhanger as Dumoulin thrives in them having taken silver in the Olympics last month.
Results from the Tour of Britain after Friday's sixth stage, a 150-kilometre ride from Sidmouth to Haytor:
Wout Poels (NED) Team Sky 3hr 56min 15sec, 2. Rohan Dennis (AUS) BMC
Racing Team at 7sec, 3. Tom Dumoulin (NED) Team Giant-Alpecin 8, 4.
Dylan Van Baarle (NED) Cannondale-Drapac 12, 5. Xandro Meurisse (BEL)
Wanty - Groupe Gobert 17, 6. Nicolas Roche (IRL) Team Sky same time, 7.
Tony Gallopin (FRA) Lotto Soudal s.t., 8. Stephen Cummings (GBR)
Dimension Data 21, 9. Erick Rowsell (GBR) Madison Genesis 31, 10. Gorka
Izaguirre (ESP) Movistar Team
1. Stephen Cummings
(GBR) Dimension Data 27hr 04min 11sec, 2. Tom Dumoulin (NED) Team
Giant-Alpecin at 49sec, 3. Rohan Dennis (AUS) BMC Racing Team 51, 4.
Tony Gallopin (FRA) Lotto Soudal 53, 5. Dylan Van Baarle (NED)
Cannondale-Drapac 57, 6. Xandro Meurisse (BEL) Wanty - Groupe Gobert 58,
7. Nicolas Roche (IRL) Team Sky 1min 06sec, 8. Ben Swift (GBR) Team Sky
1:14, 9. Jacopo Mosca (ITA) Trek-Segafredo 1:20, 10. Guillaume Martin
(FRA) Wanty - Groupe Gobert 1:24