Ott Tanak inched into an early Rally Germany lead over Thierry Neuville, as the pair left their World Rally Championship rivals trailing on Friday morning.
Hyundai driver Neuville had snatched first place from Thursday evening pacesetter Tanak's Toyota by going quickest on the opening Stein und Wein stage, taking a 0.7-second lead.
But Tanak - who is chasing a third straight Germany victory and already leads the WRC standings - retaliated with stage wins on Mittelmosel and Wadern-Weiskirchen, putting him 3.2s clear as they headed for midday service.
Reigning champion Sebastien Ogier is already 13.7s off the lead in third place with an understeer issue in his Citroen, and hinting that he has no idea how to get the car closer to the lead pair's pace.
Kris Meeke is just 0.1s ahead of Dani Sordo in the battle for fourth, with Jari-Matti Latvala only 1.9s further back.
Esapekka Lappi and Andreas Mikkelsen are also closely matched - 0.4s splitting them in seventh and eighth.
M-Sport's honour already depends on Elfyn Evans's inexperienced stand-in Gus Greensmith in ninth place, as his team-mate Teemu Suninen's Ford stopped on the morning's first stage with an as yet unexplained technical problem.
Toyota is fielding a fourth WRC entry on this event for its rising star Takamoto Katsuta.
He currently runs outside the top 10, behind the leading WRC2 cars - which are headed by Kalle Rovanpera in 10th overall.
Leading positions after SS4
|1||Ott Tanak, M.Jarveoja||Toyota Gazoo Racing WRT||Toyota||30m51.5s|
|2||Thierry Neuville, N.Gilsoul||Hyundai Shell Mobis WRT||Hyundai||3.2s|
|3||Sebastien Ogier, J.Ingrassia||Citroen Total WRT||Citroen||13.7s|
|4||Kris Meeke, S.Marshall||Toyota Gazoo Racing WRT||Toyota||17.0s|
|5||Dani Sordo, C.del Barrio||Hyundai Shell Mobis WRT||Hyundai||17.1s|
|6||Jari-Matti Latvala, M.Anttila||Toyota Gazoo Racing WRT||Toyota||19.0s|
|7||Esapekka Lappi, J.Ferm||Citroen Total WRT||Citroen||24.3s|
|8||Andreas Mikkelsen, A.Jager||Hyundai Shell Mobis WRT||Hyundai||24.7s|
|9||Gus Greensmith, E.Edmondson||M-Sport Ford WRT||Ford||41.3s|
|10||Kalle Rovanpera, J.Halttunen||Skoda Motorsport||Skoda||1m39.8s|