Hello and welcome to live coverage of stage 18 of the Tour de France - the second of two Alpine stages that could well decide who ultimately wins the yellow jersey. It's a 179.5km ride from Briancon to the Col d'Izoard, where we will witness the first ever summit finish on this mythical climb.

Barguil and Contador have joined forces and they're reeling in and passing the remnants of the break. Contador has found Bauke Mollema, who was in the break, and the two Trek riders will join forces. Back with the yellow jersey group, and Aru, Martin, Meintjes and Yates have managed to rejoin.

Warren Barguil attacks from the main pack with the gap down to two minutes for Atapuma. The Frenchman is followed by Alberto Contador, who is still hungry to get something from this Tour.

Atapuma has caught and passed Lutsenko on the front of the race.

Aru in trouble! The Italian national champion is slipping back - as is Martin, Yates and Meintjes...

Sergio Henao of Team Shy has been dropped by the main pack - as has Mathias Frank and Alexis Vuillermoz of Ag2R-La Mondiale.

Atapuma is now closing in on Lutsenko and must be the favourite for the win today, what with his climbing pedigree.

Meanwhile, back with the race and Atapuma ups the tempo from this chasing group - and he's pulling away from both Gallopin and Navarro.

Another five-time Tour winner's reign ended on the Izoard eleven years later when Frenchman Bernard Hinault conceded the yellow jersey to the American Greg LeMond, who powered clear of his La Vie Claire team-mate in the Casse Déserte. LeMond caught rival Urs Zimmermann and the pair finished three minutes ahead of an abject Hinault. That night in Briançon, LeMond and Hinault had their much publicised spat ahead of the apparent truce one day later, which manifested itself in their infamous arm-in-arm finale on Alpe d’Huez. Three years later, the American return to the climb and - this time in yellow - gained 13 precious seconds over his big rival Laurent Fignon in a stage that ended in Briançon. One day later, LeMond lost the jersey to Fignon again - only to regain it a few days later on the streets of Paris by just eight seconds. So, you could say that the Izoard once again proved instrumental.

Part of the Izoard's mystique comes in its knack of calling time on the careers of some of cycling's most treasured figures. In the same way that Court No.2 at Wimbledon has built up a reputation for being the graveyard of champions, so too has the Izoard hammered a fair few nails into the coffins of the seemingly immortal. Eddy Merckx’s era-ending fall on 14th July 1975 at the hands of Bernard Thévanet was likened to that of the Bastille. One day earlier, the great Belgian had conceded the race lead to his French rival after his dramatic défaillance on the climb to Pra Loup. But with a gap of just 58 seconds separating the two, there was all to play for in stage 16 on the Izoard. After a series of attacks on the early slopes, Thévanet dropped Merckx and rode through the Casse Déserte with a 2’25” advantage before finishing alone in Serre-Chevalier to all but end the reign of King Eddy”. While Merckx kept battling to Paris, Thévanet had won the Tour on the Izoard.

Still 10 clicks to go for Lutsenko, who has 43 seconds to play with ahead of Atapuma, Navarro and Gallopin. They have just passed through the hamlet of La Chalp. The main yellow jersey pack is 3:30 down.

Tony Gallopin has managed to catch Atapuma and Navarro. Meanwhile, back in the pack, Ag2R-La Mondiale still set a fast tempo with Froome's Sky army just behind. Barguil is still here - and the polka dot jersey shakes the hand of KOM rival Thomas De Gendt when the Belgian is reeled in and passed following his cameo in the break earlier on.

Two kilometres from the summit of the southern side there are memorial plaques laid down by L’Équipe to commemorate the two riders most readily associated with the Izoard: Italy's two-time Tour winner Fausto Coppi and French triple Tour champion Louison Bobet. Between 1949 and 1954 – when the road was just a rustic dirt track and riders had to dodge sharp flints as well as the glare of the sun as they toiled up the backbone, over the bare shoulders and towards the frowning brow of the mountain – both men soloed over the summit after making decisive attacks on the Izoard (Coppi twice and Bobet three times).

Gautier peels off the front, his work for the day done. Meanwhile, Atapuma and Navarro have attacked from the chasing group in a bid to reel in lone leader Lutsenko.

The pace is pretty punishing in the pack - and even Warren Barguil looks to be struggling. No surprise: he already has his stage win, plus the polka dot jersey in the bag.

Meanwhile, back with the peloton and numerous riders are being shelled out the back already - including Oliver Naesen, who was pace-setting for Bardet earlier, and Esteban Chaves, who is still fighting back from injury earlier in the season. AG2R-La Mondiale still front the peloton through Cyril Gautier, who has dropped back from the break to help pave the way for his team-mate Romain Bardet who, like Rigo Uran, trails Froome by 27 seconds on GC.

Lone leader Alexey Lutsenko (Astana) is onto the final big climb of this year's Tour de France - the HC Col d'Izoard (14.1km at 7.3%).

Edet may be struggling but his team-mate Navarro has just launched an attack from the chasing pack - sparking a response from Atapuma and some of the others.

Edet is already starting to struggle ahead of the climb proper. Lutsenko drops his companion and rides to the foot of the Izoard alone.

Edet takes on a gel and a sticky bidon from the Astana team car of his fellow escapee, Lutsenko. A nice touch. They have 32 seconds on the Gallopin chasing group, 1:30 on the rest of the break and 4:30 over the pack.

Lutsenko and Edet have dropped Hardy. They have 4:45 over the pack and so the winner may not necessarily come from the break - especially once the GC battle explodes on the Izoard.

Further back in the main body of the break - who trail the front of the race by about 1:20 - and there is some real climbing calibre. Riders to watch include Pauwels and Cummings of Dimension Data, Mate of Cofidis, Durasek of UAE Team Emirates, Roche of BMC, Talansky of Cannondale-Drapac and Gautier of Ag2R-La Mondiale.