Faro - Mikko Hirvonen closed in on a first victory as a Citroen driver when he extended his Rally of Portugal lead to over a minute on Saturday.
The Finn, who was runner-up in the 2011 world championship to Sebastien Loeb, will take a 1:11 lead over Norway's Mads Ostberg into Sunday's final day and a 1:41 advantage on Russia's Evgeny Novikov.
"It's been good today," said Hirvonen, who has got to the top of the leaderboard despite not winning a stage in this year's race.
"We managed to take some time out of the others. The lead is a little bigger after a very steady and safe drive.
"We need to make sure we're still there at the end of the rally because there is still a long way to go. I've been listening to every sound and every knock the car has made."
Ostberg's hopes of catching Hirvonen were hampered when his car developed an engine problem on stage 13 and he lost precious power and time.
"We hoped to take some time off Mikko but we haven't been able to do that," he said. "We will concentrate on second position and just try to continue with a steady run."
Norway's Petter Solberg, driving a factory Ford, won four of the day's six specials to move into fifth overall.
That marked a remarkable turnaround for Solberg, who had been down in 11th place on Friday morning after slipping off the track.
Rally of Portugal results on Saturday after the end of the third day's action:
1. Mikko Hirvonen (FIN/Citroen DS3) 2h 59:33.6
2. Mads Ostberg (NOR/Ford Fiesta RS) at 1:11.9
3. Evgeny Novikov (RUS/Ford Fiesta RS) 1:41.2
4. Nasser Al Attiyah (QAT/Citroen DS3) 6:10.1
5. Petter Solberg (NOR/Ford Fiesta RS) 6:26.5
Stage winners: Petter Solberg 6 (SS1, SS2, SS12, SS13, SS14, SS15), Latvala 1 (SS3), Tanak 1 (SS4), Sordo 5 (SS5, SS6, SS7, SS11, SS16)
Note: Stages 8-10 on Friday cancelled.