The Tour de France's team time trial is so critical teams have ridden it up to three times to be ready. For a team that suffers, the gaps could "could quickly be minutes" and "it could be damaging" for the overall classification.
The stage three time trial stretches out to the west of Cholet through the Maine-et-Loire. Team Sky and other strong teams will use the 35.5-kilometre stage to hammer down their rivals.
"In the big picture, it's quite important," Sunweb sports director and time trial guru, Luke Roberts explained.
"There can be quite big time losses if it goes wrong for a team, it can quite quickly be minutes. There are parts that are really fast. If you are down to four to five riders early, it can be damaging."
"I see BMC, Sky and Mitchelton clearly ahead of anyone else," Matt White, said of the favourites that included his Mitchelton-Scott team with Adam Yates. "Then Sunweb and Quick-Step in the other groups of teams.
"It's not a short TT, there will be gaps and there will be some teams more equipped than others for it.
"You have to know your strengths and weaknesses. We have a lot of TT riders here. We are confident we can get the best out of them."
Roberts added: "All the days in the first nine are important ones. We saw in stage one already what that extra investment and energy and commitment can bring. There will be more of that, all the way through to the cobbles of Roubaix [stage nine], so the guys who invest will benefit."
Sunweb have time trial world champion Tom Dumoulin racing for the overall classification. Mitchelton back Yates, Sky have four-time winner Chris Froome, and BMC Racing bring Richie Porte.
"Like with any time trial, you can gain a lot of time," said Paolo Slongo, Bahrain-Merida sports director and coach for Vincenzo Nibali.
"Now the gains in the climbs are less and less, but in the time trials or the team time trials, you gain more time. Like on a pavé stage on Sunday. So we didn't leave anything to chance. OK, we are not going to win, but at least we are going to limit the losses as much as possible."
Nibali, the 2014 Tour winner, and his seven team-mates rode the course twice Wednesday and again on Thursday.
"It's a fast time trial," Slongo added. "There's an 800-metre ramp right after the start, then a long 'French flat' – all up and down – and 10 kilometres to the finish with another little ramp. Even if it is short, everyone is going all out there.
"The winning average will be around 56. There's not any hard curves where you have to slow way down and re-start."
"It's a fast one, not too technical," White added. "The only technical aspect is the roundabouts. It can complicate things getting the guys fast around the roundabouts, but I like it and it's a good one for us. We are certainly going to be in the mix tomorrow."
"It's a really fast one," said Bauke Mollema (Trek-Segafredo). "A lot of roundabouts, then it's up and down the whole time. It's rolling so you take the climbs with a lot of speed. In the end, with seven to eight kilometres to go, there is a steep climb, so there might be a moment where riders can lose their team-mates, so it's important to stay together."
Mitchelton-Scott bring a strong time trial team, but riders like Mikel Nieve and Yates will suffer. White plans for them take fewer and shorter pulls at the front.
"We brought a team to support Adam so it's not Adam's job to perform tomorrow but to arrive to the finish line with the others," White said.
"He is 20 kilograms less to some of these big guys, so his role is to get through unscathed and survive because you can make mistakes as a small guy with the big punchy guys. The difference between a team riding for the win and one for fifth place is a lot."
"It's definitely not equal pulls, we try to find the balance," Roberts said. "The stronger guys will take longer pulls, 30 seconds or more, some of the guys only commit a bit, maybe five to 10 seconds on the front. We try to predict that, tell the guys where we expect them to contribute and how much."
"I am pretty good at TTs, so I will do some good pulls like the other guys," Mollema said. "I like the team time trials, I look forward to it. We worked a lot on it. This Monday we can be a surprise."
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