Norway's Petter Solberg failed to maintain the scorching early pace he set in the Corona Rally Mexico but still finished day one with a narrow lead.
The Subaru driver built up a lead of over 11 seconds after winning the first four stages, but placings of third, fourth and fifth in the next three allowed his nearest rivals to cut that gap.
Finland's Mikko Hirvonen (Ford) will start day two just 4.8 seconds back in second while Citroen driver Sebastien Loeb, of France, also closed to within 10 seconds of the leader after being fastest on the fifth and sixth stages.
Ireland's Gareth McHale finished day one in an excellent seventh place in a Ford Focus.
Solberg, bidding to bounce back from a nightmare start to the year after failing to score points in Monte Carlo and Sweden, blamed worn tyres for his late losses.
"We had fitted the hardest tyres available but the fronts were bald," he told the WRC official website.
"We lost pretty much everything we had gained earlier in the day."
Those three are well clear of the rest of the field, however, with Manfred Stohl's win on stage seven still leaving him over one minute and 45 seconds adrift of Solberg.
Early drivers' championship leader Marcus Gronholm crashed out after smashing his rear suspension when he slid off the road on stage four.
