Geraint Thomas expects big showdown on La Toussuire

Team Sky's Geraint Thomas is expecting fireworks on stage 19 of the Tour de France as the general classification contenders attempt to claw back time on race leader Chris Froome.

Thomas himself sits in fourth position overall but expects to see the likes of Alberto Contador and Vincenzo Nibali stake their claim for a podium finish.

The pair attempted attacks on Thursday's stage up the Col du Glandon but couldn't escape from Froome, while Nairo Quintana has also failed to pull any time back on the yellow jersey holder.

With three categorised climbs before the ascent of La Toussuire, Thomas expects to see the breakaway play a prominent role once more, but believes the showdown will occur on the final climb.

"There is always somebody in the top seven or eight who can still be pretty dangerous on a stage like this, even if they are four or five minutes down," he told the BBC. "It's only 138km long, so it's not a huge day in the mountains and you can ride hard. I think it will be full-gas racing from start to finish.

"There's likely to be a big breakaway with more than 10 riders, Vincenzo Nibali's Astana team and Contador's Tinkoff-Saxo team too could send a man up the road.

"And Team Sky might do the same. When it comes to the final climb, each of the big contenders could have a good carrot to chase, what with the time bonus for the stage win, and people to help them down the road. We should see a big showdown."

Quintana and Alejandro Valverde sit 3:10 and 4:09 down on Froome respectively in second and third, with Thomas sitting 6:34 back in fourth.

Stage 19 is the first of two summit finishes to end the Tour de France, with riders taking on Alpe d'Huez on Saturday's stage 20 before rolling into Paris on Sunday.

Your guide to the Tour de France in the Alps