Six more days to topple Castle Froome and it's looking like it'll be a difficult task for those seeking to end his reign. Surrounded by faithful guardians, the three times champion is by far the favourite to become a four-time winner, and in doing so join a very exclusive group of legendary riders but there are still six stages, six cols and six riders in the GC play.
Stage 16 is a day for paying attention for the GC riders and only the last kilometres near the finish merit full commitment, otherwise it's for the sprinters’ teams to keep everything under control.
However, stage 17 is where the real battles begin because this will be a long fight and not one day will be enough to crack Team Sky, if cracking them is within the realms of possibility. Romain Bardet’s AG2R La Mondiale hold the cards on how this is all going to play out as they are the only ones with enough climbing talent to take on the race when it begins the brutal slopes of the Croix de Fer. If they can reduce the number of teammates Chris Froome has for the following valley and the Telegraphe that leaves the opportunity for the GC contenders to race the upper slopes of the Galiber and isolate the race leader totally. The descent to Serre Chevalier isn't technical, it's a big wide road for most of it and pedaling is required. If it's a headwind, and it usually is, it's a real struggle on your own.
The next day is probably going to be the most crucial one for Bardet, Fabio Aru, Dan Martin and Rigoberto Uran if they are to secure a sizeable lead over Froome before the Marseille time trial. They all need more than a minute on the Sky rider and even then they'll be sweating. L'Izoard is one of those places in the Tour where you feel the history and rightly so. The approach to it is a real grind and then once the bends start it's every man for himself. It's not a regular gradient, there are numerous changes to cope with and that'll suit Bardet perfectly. His problem will be wind once you get up in Casse Deserte because then if you're on your limit already that just kills you.
The biggest factor in how Team Sky manages the two mountain stages will be their three Michaels - Landa, Nieve and Kwiatkowski. They need the two Spanish climbers for the final climb each day and they need the Polish star shepherding Froome on the flatter stages and in any move than needs covering on 17 and 18. Nieve is climbing as well as the top GC contenders and even if Aru or Bardet attacks he's more than capable of taking them back but he has to be fresh enough to do that and it'll be the other teams' moves which have to expose Sky early enough. Landa is the enigma here. In a move with, say, Contador or Uran does he ride with them, does he sit on and what if he's better than Chris Froome? A possible yellow jersey and maybe a Tour win changes even the most loyal rider, so there are questions despite the reassuring noises.
Aru doesn't have the team to control anything difficult and even if the Italian re-takes the lead there'll be complete mayhem. Martin is in a similar position with his team too but the chances of him taking the lead either side of the TT are slim. As for Uran, the Colombian is the dark horse that looks most likely to push Froome the hardest on the Marseille test so all he's got to do is survive the Bardet and Aru offensives. Personally, I think Aru will fall apart and Bardet will be the one who provokes the decisions and the final result.
At the moment the challengers to Sky have been squabbling amongst themselves, chasing each other, working when they don't really have to. If they want to have a chance of the overall then they have to play the same kind of poker game Froome employed at Peyragaudes. It has to be all in or nothing because a time trial contest between those who are currently in places two till six in GC is winnable for any of them. However, with Chris Froome involved they are looking at losing three to four seconds per kilometre and the hill in the middle of the Marseille stage changes that not one bit.
For the other competitions Warren Barguil has earned the climbers jersey the hard way and barring accident will have that wrapped up well before the weekend.
Simon Yates has the measure of Louis Meintjes and will equal his brother in taking the white jersey, if not such a high GC finish.
The Green jersey competition is more difficult to predict. Kittel was looking very tired pre-rest day and the two big Alpine stages could finish him off. If he wins in Romans sur Isere then the contest with Michael Matthews is basically over but there are too many ifs for the moment.
And will Steve Cummings win a stage? Nobody knows, not even him.