Nine-time World Rally champion Sebastien Loeb underlined his mastery of the sport with an astonishing performance in his one-off comeback in Monte Carlo.
The Frenchman, who accepted an invite from Citroen to compete in the first event of the 2015 season, was 22 seconds quicker than closest rival Ott Tanak in SS1 at Entrevaux-Rouaine.
In-car split times are banned this year, which meant Loeb was unaware of his achievement - an incredible one even by his standards - until he climbed out of his car at the end of the first stage.
"I said to Daniel [Elena, Loeb's co-driver] three kilometres before the end that it felt like we were stopped," he explained. "The road was full of ice everywhere and it was very, very difficult. But I'm happy for this time."
Defending champion Sebastien Ogier (Volkswagen) was a further 8.9secs back, but redeemed himself on the 19.68-kilometre Norante-Digne-Les-Bains stage, where he was 10.7secs ahead of team-mate Jari-Matti Latvala.
That saw him finish Thursday's action 13.3secs behind his compatriot Loeb, who was third fastest in SS2.
Loeb is seeking an eighth Monte Carlo Rally victory, but will have to wrest the title from the grasp of Ogier, who prevailed over fellow home favourite Bryan Bouffier last year by a margin of just over one minute.
On Friday the field, which includes returning ex-Formula One driver Robert Kubica, will compete in five further special stages across a combined distance of 123.1km.