Defending champion believes race could be won and lost on time bonuses, as opposed to Sunday's ITT.

Bradley Wiggins admitted that his Tour of Britain defence hangs in the balance following this afternoon’s finish atop The Tumble

The unfancied Edoardo Zardini (Bardiani-CSF) rode to a surprise victory in Wales. However, Michal Kwiatkowski (Omega Pharma-Quick Step) beat the Team Sky rider to the line, and holds an 11-second advantage over the reigning champion.

Wiggins now says the Polish rider is his main rival in the race, particularly given that both should ride well in Sunday’s 8.8-kilometre time trial.

“The time gap’s not too bad [to Kwiatkowski] and it’s all to play for in London,” said Wiggins.

“I’m in a good place. If it stays pretty close like this until London we will give ourselves a good chance. Eight kilometres doesn’t sound a lot but it’s like a pursuit and that will favour me more than other riders.

“Kwiatkowski is a good time trialist so it’s going to be tight. It’s doable, it’s not impossible. I think 11 seconds to Kwiatkowski is going to be touch and go. It just depends what kind of day he is on – I thought he would take more today.”

Wiggins is also wary that time bonuses may have a say on who takes the overall victory on Sunday.

There are three intermediate sprints during each stage for the next four days, plus one in the final-day criterium race around London, that have three, two and one second available.

Ten, six and four seconds will be available for the top three on stages four to seven, although these are reduced for the top three on stage 8b.

“You never know, the time bonuses really change things,” he added. “But there are still three or four days now [that could change things]. That run-in to Brighton, and Bristol. It could all change. It’s not a foregone conclusion.”

Asked about the chances of Zardini , Wiggins replied: “I didn’t even know who he was to be honest. I think he surprised a few people today.”

Sky DS Nicolas Portal was relived that Wiggins did not move into yellow today, particularly following Ian Stannard’s departure from the race yesterday through injury.

“I think it’s good, as we only have five riders and you don’t want the weight of the race on your shoulder,” said Portal.

“We saw yesterday that no team wanted to ride and now the race is a shared job for a few teams, which is better for us.”