(CNN) -- Sebastien Loeb closed on a record sixth straight world rally title as he extended his lead after the second day of the season-ending race in Wales.
The French ace leads current championship leader Mikko Hirvonen of Finland by 30.2 seconds with just four special stages remaining on Sunday in the Wales Rally GB.
Victory will secure the crown for Citroen's Loeb, who trailed Hirvonen by a single point going into the decider.
Loeb held a 5.3 second lead after Friday's opening day, but this was cut to just 2.9 seconds when his Ford Focus rival won the first special stage of the day.
But thereafter the reigning champion turned on the style to steadily increase his advantage, completing a superb day with an emphatic win on the 12th special stage.
"Early in the day I was able to build a good gap to Mikko, although this afternoon he was closer because the roads were muddier," he told the official world rallying Web site www.wrc.com.
"I've had a very good drive, made no mistakes and now here we are, with a good lead for tomorrow. Everything's perfect for the moment."
Hirvonen was disconsolate after seeing Loeb build such a commanding advantage.
"It's not been a good day and I still don't understand how we lost so much time earlier.
"Tomorrow is the last day of the year and I've no option but to go flat-out."
Loeb's Spanish teammate Dani Sordo completed a fine day for Citroen by moving into third place above Norway's Petter Solberg, building up a 24 second advantage by the end of the day.
The race is the 65th edition of the famous British rally which was first staged in 1932 and now takes place mainly on forestry roads in Wales, with the ceremonial finish in Cardiff.