London - Bradley Wiggins has accepted his Tour of Britain title defence was nearly at an end after Poland's Michal Kwiatkowski secured the overall lead with a dramatic stage win on Wednesday.
Kwiatkowski won the sprint for the line at the end of the 184.6-kilometre route from Worcester in the English Midlands to Bristol on the south-west coast to take the leader's yellow jersey.
Dutch racer Albert Timmer (Giant-Shimano) took second place in the stage, with Belgium's Dylan Teuns (BMC Racing) third.
The time bonus which accompanied the win saw Kwiatkowski move three seconds ahead of Italy's Edoardo Zardini (Bardiani CSF) in the overall standings.
Team Sky's Wiggins, the 2012 Tour de France champion and 2013 Tour of Britain winner, is now 27 seconds behind in sixth place overall.
"I'm still up there but on paper first place has gone now," Wiggins told ITV.com.
"I can't see myself getting 27 seconds on Kwiatkowski, but the podium is only 12 seconds away," added Wiggins, the first Briton to win the Tour de France.
"He only has to have a puncture in the time trial. I wouldn't say the GC (general classification) is over because finishing up there as the defending champion is important."
The stage was decided in the final 3km when Timmer tried to break away before being closed down by Jack Bauer (Garmin-Sharp) before Kwiatkowski and three other riders caught them up, with the Polish cyclist powering past Bauer.
The race concludes in London on Sunday.