Leopold Koenig (Team NetApp) claimed victory on the 189.8-kilometre route from Welshpool to Caerphilly yesterday and Tiernan-Locke (Endura Racing) finished second to assume the race leader’s gold jersey with two days of racing remaining.
The 27-year-old from Plymouth, who is rumoured to be joining Team Sky in 2013 and has been named in the British team for next week’s road World Championships, began the day in sixth place, 24 seconds behind Leigh Howard (Orica-GreenEdge).
But now Tiernan-Locke, who received a six-second time bonus for placing second, has a 13-second lead over Howard ahead of today’s seventh stage from Barnstaple to Dartmouth.
The eight-stage race concludes with tomorrow’s Surrey route from Reigate to Guildford.
Tour de France winner and Olympic time trial champion Bradley Wiggins was a non-starter in Welshpool because of a stomach problem after an eventful fifth stage to Stoke-on-Trent for Team Sky, which saw Mark Cavendish relinquish the race lead to Howard.