Lilian Calmejane broke away to win a gruelling stage eight of the Tour de France in his homeland and Chris Froome maintained his overall lead.

Calmejane went out on his own 17 kilometres from the end of the 187.5km route from Doule to Les Rousses on Saturday and eased to his first stage win in the famous race by 37 seconds despite suffering from cramp.

An ecstatic Calmejane shook his head and raised his arms as the 24-year-old climber crossed the finishing line in the ski resort to become the second Frenchman to win a stage in the 2017 Tour, following Arnaud Demare's success on stage four.

The 24-year-old Direct Energie rider almost came to a halt 5km from the finish in the heat as a tough day in the saddle caught up with him, but he still had a bit left in the tank.

Robert Gesink finished second, with Guillaume Martin third, and Froome maintained his 12-second advantage over Geraint Thomas on a savage day that started frantically, but finished with no change for the leading contenders.

Froome and his rivals for the yellow jersey were 50 seconds back from Calmejane, preserving some energy with a fearsome stage nine to come on Sunday.

Thomas cut his knee after falling and Froome rode into the grass when he failed to negotiate a right turn, but the Team Sky duo recovered to finish comfortably in the peloton.

It was very much Calmejane's day, though, attacking with 6km to go on the last category one climb and taking the polka dot jersey in style with a magnificent solo ride.

Friday's runner-up Edvald Boasson Hagen and Sylvain Chavanel were among the riders to mount early assaults and Gesink tried to reel Calmejane after he made his move, but did not come close to denying the Frenchman.

GOOD DAY/BAD DAY

While Calmejane had a day to remember on home soil, it was one to forget for his compatriot Demare.

The FDJ rider endured an almighty struggle in the first climb of the day and finally crossed the line over 37 minutes after the winner.

With no movement among the main contenders for the overall title, it was Calmejane who took the limelight.

STAGE RESULT

1. Lillian Calmejane (Direct Energie) 04:30:29
2. Robert Gesink (Lotto NL-Jumbo) +0:37
3. Guillaume Martin (Wanty-Groupe Gobert) +0:50
4. Nicolas Roche (BMC Racing) +0:50
5. Roman Kreuziger (Orica-Scott) +0:50

GENERAL CLASSIFICATION

1. Chris Froome (Team Sky) 33:19:10
2. Geraint Thomas (Team Sky) +0:12
3. Fabio Aru (Astana) +0:14

POINTS CLASSIFICATION

1. Marcel Kittel (Quick-Step Floors) 212 points
2. Arnaud Demare (FDJ) 182 points
3. Michael Matthews (Sunweb) 140 points

KING OF THE MOUNTAINS

1. Lillian Calmejane (Direct Energie) 11 points
2. Fabio Aru (Astana) 10 points
3. Dan Martin (Quick-Step Floors) 8 points

NEXT UP...

The riders face a hugely demanding day on Sunday, with one of three Hors Categorie climbs coming right at the start in a ninth stage that has been billed as the toughest of this year's race.

An ascent of the Mont du Chat comes late in the 181.5km route from Nantua to Chambery, which includes as many of seven climbs in all and could have a huge say in how the Tour pans out.