Ogier, an eight-time winner in the French Alps, opened the series' pioneering new hybrid-powered era by winning both speed tests in his Toyota GR Yaris to build a 6.7sec lead.
Snapping on his heels was seven-time Monte winner Loeb. In his first WRC drive for more than a year, the French master finished second in both stages in M-Sport Ford's Puma.
It was hard to imagine a more daunting opening to the sport's new generation. Two stages on winding roads in darkness, including the crossing of the iconic Col de Turini, with frost settling on the asphalt and drivers yet to learn the mix of electric and combustion engine power in competition.