The M-Sport Ford driver shared the lead with Volkswagen's Sebastien Ogier and twice with Citroen's Mikko Hirvonen, but moved himself 5.2s clear of the championship leader after SS6.
Hirvonen had replaced Ogier as the joint leader after victory on SS4, but suffered a disastrous SS5. With the cars being sent out in groups of four for a rain-affected second Himos leg, Hirvonen - the last of the leaders to run, 30s after the rest - blamed deteriorating stage conditions as he lost 20s and dropped to fifth.
Ogier also struggled to match Neuville's pace on the fifth stage, slipping behind the Belgian's team-mate Mads Ostberg - though he did manage to reclaim the position on SS6.
The Norwegian's SS5 victory had brought him to just 2.5s behind Neuville, but a sluggish run on the Super Special cost him time, and left him 8.9s adrift.
Hirvonen also regained a position on the Super Special, at the expense of Juho Hanninen. He is now just 0.5s ahead of Kris Meeke, who rounded out his first day in the DS3 in sixth place.
Jari-Matti Latvala's day ended early after the completion of SS4. The Finn's Polo was damaged after hitting a rock on SS2 and, despite hobbling through the third and fourth runs, he withdrew before the start of the day's penultimate stage.
Jari Ketomaa's domination of WRC2 continued in the R5 Fiesta. He boosted his lead to 24s, with Robert Kubica leading the chase. The Pole had overtaken Elfyn Evans earlier in the evening.
The second day begins with SS7 on Friday morning at 06:48 GMT.
- Sports & Recreation
- Mikko Hirvonen
- Sebastien Ogier