Sebastien Ogier more than doubled his lead to almost half a minute at the Mexico Rally, which organisers said would finish a day earlier than scheduled due to the coronavirus pandemic.
"In agreement with teams, the FIA and WRC Promoter, the organising committee has decided to bring forward the end of the event after the Rock and Rally special stage on Saturday evening," said Mexico Rally director Patrick Suberville.
"This will allow teams and the media to return to their countries with the anticipation of the imminent closure of their borders because of Covid-19."
France's multiple world champion Ogier, seeking a sixth Mexico win, took Saturday morning's opening stage and built up a 28.1-second lead over Teemu Suninen in a Ford after 17 stages.
Reigning world champion Ott Tanak, driving a Hyundai, is placed third at 31.2sec with four specials remaining, after the decision to scrap Sunday's concluding three stages.
Ogier's Toyota Yaris teammate Elfyn Evans was next at 58.6sec.
Welshman Evans arrived in Mexico atop the drivers' standings after success last month in Sweden.