MEGèVE (FRANCE) - Leader Chris Froome's knee and back will play a pivotal role in how Saturday's penultimate -- and likely decisive -- Tour de France stage pans out.
Britain's Christopher Froome (C), wearing the overall leader's yellow jersey, waits for the start of the 19th stage of the Tour de France on July 22, 2016
The 31-year-old Briton has been pounding dominantly towards a third Tour title with not a single rival able to slow the Sky juggernaut.
At least that's how things seemed until the yellow jersey wearer crashed on a slippery descent during Friday's 19th stage.
Battered and bruised, his jersey torn and riding a team-mate's bike to the finish, Froome lost only a handful of seconds to some of his rivals, while actually gaining time on others and extending his overall lead.
But it is one thing to soldier on in the final 20km of a stage when the adrenaline is high, and quite another to tackle 146.5km of Alpine terrain with four categorised climbs if you're stiff, sore and in pain.
What's more, it's expected to rain all day, creating more treacherous descents.
Froome assured fans he was fine following Friday's stage but he took to the podium with a heavily bandaged knee.
If ever there is a chance that this Tour race is not yet run, it will depend on Froome's physical condition on Saturday.
"I'm OK, I'm lucky nothing is seriously injured. I lost some skin and banged my knee a little bit but today I'm grateful to have that four-minute advantage to fall on a little bit," he said following Friday's stage.
"Tomorrow (Saturday) will be hard, I'm sure I'm going to be a bit sore and stiff from today but hopefully I can rely on my team-mates and just one last push again to get through tomorrow's stage now."
Two years ago he crashed during the Criterium du Dauphine while in the lead and although he got to the stage's end still in contention, the next day he suffered badly and lost several minutes, dropping out of the top 10.
While his 4min 11sec advantage over second-placed Frenchman Romain Bardet should afford him ample breathing space, the raging battle for the other two podium positions should ensure the pace is high on Saturday and the attacks are numerous.
Fabio Aru showed on Friday he's prepared to push the pace to try to drag himself onto the podium.
He's sixth and just over a minute and a half off the podium so cannot afford to play a waiting game if he wants to claim a top-three finish.
Bardet and third-placed Nairo Quintana are separated by only 16sec with Adam Yates another 19sec further back, meaning those three should be trying to test each other.
Bardet is the best descender of the three, meaning the other two will need to attack on the final hors category climb before the 12km descent to the finish in Morzine in order to displace the Frenchman.
Fireworks will likely be going off all around Froome, what remains to be seen is whether or not he has the condition to keep calm and stay in control.