With snow threatening the full running of the Giro d'Italia's two mighty tapponi to Val Martello and Tre Cime di Lavaredo later in the week, Thursday's stage 18 mountain time trial from Mori to Polsa has taken on an additional significance in the final reckoning.
Vincenzo Nibali (Astana) holds a lead of 1:26 over Cadel Evans (BMC) and 2:46 over Rigoberto Uran (Sky) entering the 20.6km test, which marks the beginning of the Giro's endgame. Though Nibali has appeared impregnable since taking hold of the maglia rosa at the end of week one, the mixed nature of Thursday's cronoscalata course makes it a difficult race to predict, and both Sky and BMC were bullish about their chances of challenging the Sicilian.
The time trial divides roughly into three parts. After a kilometre of flat, the road pitches up to an average gradient of 6.6% over the following eight kilometres, as far as the intermediate time check at Brentonico. The course then plateaus for four kilometres before the gradient kicks up again to an average of 6.6% for the final six kilometres, with the steepest gradients of 10% coming just over four kilometres from the summit.
By Sky performance manager Rod Ellingworth's reckoning, it's a course that would have suited Bradley Wiggins, who abandoned the race with a chest infection last week, but he is confident that Rigoberto Uran will at least maintain contact with Nibali and Evans.
"Rigo will just do the best job he can and not worry about others, and we feel quite confident he'll do a good ride. He's certainly going to hold his own," Ellingworth told Cyclingnews. "Nibali will go well on that because he can climb well, and he's time trialling well. Evans will be good too. They'll both do good rides on that course."
Given Nibali's form in the mountains, the Sicilian should - in theory - be able to gain time on the steeper sections near the summit but BMC directeur sportif Max Sciandri believes Cadel Evans' time trialling pedigree will be a benefit over the opening half of the course.
"The second part of it is going to be hard but Cadel can do very well on the first part, so we'll see tomorrow," Sciandri said. "He's up for it, we're up for it."
A mountain time trial is a test that requires teams to strike a fine balance between aerodynamics and saving weight, and that conundrum is exacerbated by the nature of the course. Unlike the Plan de Corones time trial of 2010, for instance, this is not simply a sharp grind up vertiginous slopes, and the morning reconnaissance will be far from a formality.
"I think the interesting thing will be people's equipment choice and whether some guys will ride a low-pro bike if it's light enough," Ellingworth said. "I think we will ride with a road bike and tri-bars but then again, Rigo is going to have another look at it in the morning and have a good think about what he needs to do. There are quite a few choices - wheel choices and gear choices - there's all that to be done yet."
For their part, Sciandri and BMC were keeping their cards close to their chests. "Gearing will all be chosen later, we're not talking about that now," Sciandri said.
While Thursday's time trial at least offers the certainty of a controlled environment, the battlefield for the Giro's final skirmishes has yet to be established. Snowfall above altitudes of 1500 metres means that stage 19 and 20 may have to be altered significantly, although neither the BMC nor Sky camps were looking beyond the 20.6 kilometres that separate Mori and Polsa.
"There's nothing we know about that. It's one day at a time, especially at this point in the Giro," Sciandri said, while Ellingworth believes any alternative route will still offer scope for attacking.
"You can't do anything about it, you've just got to go with it," Ellingworth said. "I imagine the organisers are fretting at the minute but we'll do what we need to do and I think they'll still make it fairly hard. Whatever happens, they'll use something that will make those stages decisive enough anyway."