BP Ford team leader Marcus Gronholm has retired from leg 1 of the Rally Japan in the fourth stage of the event.

Gronholm, who had taken the lead after setting the second quickest in SS3, made a crucial error in the 2.73 kilometre Rikubetsu test, when he went off the road and dropped around a minute.

The incident damaged the roll cage inside the door on his side of the car and subsequently he had no choice but to pull out.

"The damage was too great for Marcus to continue for safety reasons and he retired from the day's action," confirmed a statement from the M-Sport-run outfit.

"The team and FIA technical officials will now examine the point of impact in greater detail to determine whether Marcus will be able to return tomorrow under SupeRally regulations."

Gronholm was bitterly disappointed, especially as it now means he is almost certain to lose the lead in the drivers' championship, as Sebastien Loeb is currently running third overall, 6.1 seconds behind Jari-Matti Latvala, who heads the pack in his Stobart Ford Focus.

"The accident happened at a third gear corner at a point in the stage where I changed my pace notes during the recce," Marcus explained.

"It's faster there this year because some trees have been cut down. I slid wide and the right rear wheel hit some straw bales. The impact threw the car down a bank into a tree stump.

"The impact was hard and on my door. The stage was covered with loose gravel and was slippery all through. It will be hard to repair the damage but the team will do everything it can."