Ott Tanak took advantage of a Sebastien Ogier spin to close to within 15 seconds of the lead of Rally Monte Carlo overnight.
The Estonian was already making in-roads into Ogier's lead in the wet conditions before Ogier slid wide at a hairpin on the penultimate stage of the day and got stuck in a ditch. The M-Sport Ford driver got some help from spectators and got going having dropped about 30 seconds.
That allowed Tanak, his former teammate, to close to within striking distance in his debut outing with Toyota.
"It feels very positive to end the first full day in this position," Tanak said. "We improved a lot today, and it is nice to be increasing in confidence with every stage. I want to continue in the same way: to keep learning all the time and to understand the car more.
"There are many mistakes happening from others so we just need to be really clever with our driving. There is definitely no need to push any more. The rally will not be decided just by pure speed: it's more about the consistency and smart decisions."
Dani Sordo remains in third place in his Hyundai with the Toyotas of Esapekka Lappi and Jari-Matti Latvala holding down fourth and fifth.
World champion runner-up Thierry Neuville enjoyed a solid day as he tried to overcome the four minutes lost on the opening stage. He is ninth in his Hyundai but closing in on those in front of him.
Andreas Mikkelsen encountered an alternator problem at the end of the first stage of the day, which couldn't be fixed forcing his Hyundai out of the rally.
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