Sir Bradley Wiggins 12th in Paris-Nice prologue

As time trial world champion, Wiggins wears the rainbow stripes when competing in the discipline

Britain's world time-trial champion Sir Bradley Wiggins finished 15 seconds off the pace in the Paris-Nice prologue.

Team Sky rider Wiggins completed the 6.7km time trial in seven minutes 55 seconds, the same time as his team leader Richie Porte.

Fellow Team Sky rider Geraint Thomas was the quickest Briton in 7:54.

Poland's road world champion Michal Kwiatkowski won, despite clocking 7:40, the same time as Rohan Dennis, at the start of the week-long race.

Australian Dennis, who broke the world hour record on the track last month, finished ahead of another time-trial specialist, Germany's three-time world champion Tony Martin.

"It was a fast and relatively flat course and Richie is in climber mode right now so he did a great job," said sports director Nicolas Portal on Team Sky's website.

"Geraint was a bit disappointed because he missed a corner. He lost one or two seconds.

"Brad rode well but I think he was expecting more from himself. But for this short stage it's not a bad performance."

Porte and Wiggins are both previous winners of the race, which features a mix of flat and hilly stages and has been likened to a mini Tour de France.

Monday's first stage is a relatively flat 196.5km ride from Saint-Remy-les-Chevreuse to Contres.

The race ends next Sunday with another time trial, a 9.6km race to the summit of Col d'Eze on the outskirts of Nice.