Elfyn Evans claimed two of the three Saturday morning stages to extend his Rally Chile lead as reigning world champion Kalle Rovanpera emerged as his nearest rival.
Evans, who was handed a three-second overnight lead following a change to his notional stage one time, completed a trio of abrasive gravel stages with a 11.3s margin over Toyota team-mate Rovanperä.
Hyundai's Ott Tanak slipped from second to third some 17.4s in arrears, while championship leader Thierry Neuville hauled his Hyundai from sixth to fourth [+48.8s].
Toyota's rising star Sami Pajari continued his impressive drive to hold fifth [+1m03.4s] in only his second Rally1 outing, ahead of M-Sport duo Gregoire Munster [+1m24.5s] and Adrien Fourmaux [+1m24.9s]. Hyundai's Esapekka Lappi rounded out the top eight, while M-Sport's Martins Sesks rejoined the rally after his Friday retirement.
Managing tyre wear was the main objective through Saturday's rough stages, which was reflected in the tyre choices by the crews. Four hards and two softs was the favoured package, while Sebastien Ogier gambled by taking four softs and two hards.
It appeared Ogier's choice was inspired, as crews tackled a damp mountainous run through stage seven (Pelon, 15.66km) as the Frenchman set a blistering time from second on the road.
It stood until rally leader Evans completed his pass, pipping his team-mate by 0.9s to claim a second stage win of the event. Importantly, Evans was 4.1s quicker than Tanak to extend his rally lead over the Hyundai to 7.1s.
Rovanpera appeared much more comfortable on the abrasive gravel as the Finn closed to within 4.4s of second-placed Tänak.
"I would say it is a bit better for me today feeling-wise, let's see if we can find some speed today," said Rovanperä.
"It is not going to be easy the whole loop, managing the tyre wear is key and also driving in the line.
"It is quite humid in the car today, I don't know why I'm sweating so much, maybe I need to go for a run."
Championship leader Neuville was only two tenths of a second slower than Tanak, which helped the Belgian climb to fifth overall. Munster, who admitted he wasn't fully awake, slipped to sixth after dropping 27.4s on the tricky slippery roads.
Lappi was also caught out by the slippery conditions resulting in the Finn ripping the front bumper off his i20 N.
"It was tricky to see, it stayed in front of me and turned up - I saw a cut and used that to rip it [the bumper] off," said Lappi.
Stage eight (Lota 25.6km) provided a twist in the title race as Ogier, sitting 38 points behind leader Neuville, retired from the day after hitting a rock 400 metres from the finish.
Ogier hit the rock on the entry to a slow left-hander but the impact seemingly broke something on his GR Yaris, which slowly careered wide into a bank on the exit of the corner.
Ogier and co-driver Vincent Landais quickly leapt out of the car to assess the damage but it appeared their day was over.
The rally leaderboard also underwent a bit of a shake-up as Rovanpera delivered an impressive stage win after navigating through sections of low cloud, 9.7s faster than rally leader Evans, who felt he "didn't drive to his correct rhythm".
The effort moved Rovanpera into second overall, only 1.6s behind team-mate Evans, but ahead of Tanak, who lost time to a half spin at a right hander.
"That's a good [run] - the stage is really nice, the road is really rough on the tyres and you need to take a bit of care," said Rovanperä.
Neuville continued his charge to end the test 9.4s behind fourth-placed Pajari.
Evans saved his best drive of the rally to date for the morning's final stage (Maria las Cruces, 28.31km), held in tricky foggy and damp conditions.
The Welshman posted a blistering effort, while managing his tyres, to stop the clocks in the rally's longest test eight seconds faster than anyone else to take the stage win.
Despite revealing that he was carrying a serious problem, Neuville emerged as his nearest rival as the Hyundai driver moved ahead of Pajari into fourth overall.
Tanak could only complete the stage 9.3s adrift with Rovanpera a further 0.2s back, which helped Evans into an 11.3s lead over the latter.
In WRC2, Oliver Solberg leapt into the class lead (ninth overall) after the Swede overhauled Yohan Rossel on stage nine. If Solberg wins the rally, he will claim the WRC2 title.
The crews will repeat the stages this afternoon to complete Saturday's leg.
