Mikko Hirvonen led a Ford one-two after the first day of the title-deciding British rally on Friday with teammate Marcus Gronholm ahead of Citroen's championship favourite Sebastien Loeb.

Frenchman Loeb was taking no risks in the murky forests of south Wales, knowing that he need only finish in the top five on Sunday to secure his fourth world title in a row.

Loeb leads Gronholm by six points in the standings and has won eight rallies this season to the Finn's five. Ford have already clinched a second successive manufacturers' title.

Hirvonen won five of the day's six stages to go 39.6 seconds clear of compatriot Gronholm, a double world champion who is retiring after the season-ending rally.

Loeb, on course to equal retired Finn Tommi Makinen's record of four championships in a row, was in third place a further 18.3 seconds adrift.

The champion would have to lose more than four minutes to drop out of the top five with sixth-placed Matthew Wilson, the leading Briton in a Ford, five minutes and 1.3 seconds behind Hirvonen.

Australian Chris Atkinson was in sixth position, five minutes down in his Subaru.

Gronholm, who crashed out of the previous rally in Ireland, shared the fastest time with Loeb in the day's fifth stage before the Citroen driver suffered fog light problems and dropped back in the dark.

"I don't need to push to the maximum," Gronholm said at the midday break, knowing that it would be something exceptional for him to beat Loeb to the title. "We just need to wait and see what happens to Sebastien."

Stobart Ford's Jari-Matti Latvala, another Finn, had featured strongly for most of the day but lost a lot of time on the final Rheola 2 stage when his car's wipers failed in rain and total darkness.

Subaru's Norwegian Petter Solberg, winner four times in Britain in the last five years, took over in fourth place.

"It will be a bit stupid in my situation to take lots of risks to try and win here," Loeb had said before the start.

"I've not started a rally in this position before - normally when I start I want to go as fast as possible and go for the victory."

The Frenchman missed last year's British round, won by Gronholm, after breaking his arm falling off a mountain bike in a training accident.

Two spectators were taken to hospital in Swansea with minor injuries after a privately-entered Subaru driven by Briton Simon Harraway went off the forest track in the opening stage. The crew were unhurt but the stage was stopped after the incident.

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