The 23.5km time trial between La Tour-du-Pin and Bourgoin-Jallieu will be the first time the general classification contenders get to set a marker against each other so far in the race.
Froome currently sits 1-09 down on race leader Thomas De Gendt (Lotto-Soudal), who has worn the yellow jersey since taking a breakaway victory on the opening stage.
But when Froome, arguably the best tester of the GC contenders, was asked if he thought he might be in the lead after stage four he said: “What is it a minute or something to De Gendt? I don’t think that’s possible he’s going well at the moment.”
The defending Dauphiné champion said that Katusha-Alpecin’s German powerhouse Tony Martin would be “the man to beat” but that he was more interested in how he did compared with the other GC contenders.
“The time trial is, of course, a huge dynamic of the race here,” Froome added.
“Whoever gets time in terms of the GC battle won’t have to go on the offensive [in the mountains]. It’s also an important test for what’s to come in the Tour, we’ve got a similar prologue in Düsseldorf and a similar TT in Marseille at the end of the Tour. It’s good practice, a good hit out, ahead of that.”
Froome added that he was hoping to have a better outing on the time trial bike than his last one in competition in the Tour de Romandie when he finished 38 seconds down on Richie Porte (BMC) and two seconds ahead of Simon Yates (Orica-Scott) in an 18km time trial.
The Brit said he’d already seen, over the course of the race’s first three stages, that Porte was “in great form” this week in southern France.
He added: “I’ve not seen much of Romain Bardet. I think he’s staying hidden, maybe waiting for the Mont du Chat stage [on Friday] on his home roads.”