Wellington - The Bulls team of Karl Platt and Urs Huber have lodged a protest after confusing signs led them off course in the fourth stage of the Absa Cape Epic on Thursday.
It cost them nearly 17 minutes' riding and all but ended their challenge.
They were joined in the protest by the second Bulls team of Thomas Dietsch and Tim Boehme, and the Multivan Merida team of Jose Hermida and Rudi van Houts.
They had been riding in a pack, trying to catch a break from defending champion Christoph Sauser and Olympic gold medallist Jaroslav Kulhavy.
Having started the day with a deficit of eight minutes, 49 seconds, the Burry Stander Songo team can now look forward to the remaining three stages with a comfortable cushion of 13 minutes over Platt and Huber.
It would seem that only catastrophic mechanical failure can prevent Sauser winning his fourth Epic and give Kulhavy a multi-stage title to go with his Olympic gold.
Sauser, faced with such a deficit on the start line on Thursday morning, spoke of having to take their chances and of making the race as hard as possible for the Bulls riders, who were working together to set the pace and control the race.
That chance came some 40km into the race, when Sauser decided the pace was too leisurely and stepped up the pressure.
"The Bulls riders were playing games and trying to not let me pass, but that just motivated me more," Sauser said.
"But we rode hard and then we noticed that they were dropping back. It was an important day for the Bulls and they should have stayed with us. They seem pretty tired now."
Coming onto the rapid descent into Wellington, the Songo team had built up a lead of six minutes which would have been achievement enough, but never could they have dreamed of such a lead.
"We know we have just borrowed the yellow jersey," said Sauser.
"We must now just be careful and stay focused."
Sauser had won the Epic twice with Burry Stander, who was knocked down and killed by a minibus taxi in January.
"Putting on the yellow jersey was such an emotional moment for me, especially with the Stander family there, remembering what we had done before. It is a huge motivation."
Platt and Huber had held the yellow jersey for two days. At the start line on Thursday morning they were quietly confident of holding their own.
This was the second day in a row that riders had gone off course. Sauser and Kulhavy were the victims on Wednesday, but they lost just three minutes.
According to observers, the Bulls and Merida team followed signs left over from the recent "Grape Escape" race and then picked up signs relating to Friday's stage, sowing further confusion. Motorcycle cameramen also spoke of the confusing signs.
The destruction of that chasing group allowed the third group to make their move. Second place in the stage was taken by the team of Marco Fontano and Manuel Fumic, who had been placed third and seventh respectively in the London Olympics.
The South African team of Philip Buys and Matthys Beukes finished third, lifting them to seventh overall, just behind Darren Lill and Charles Keey.
Friday's ride offers Sauser more hope as it is a quick 75km ride with little climbing. It features more single track racing than in any other Epic, with perfect cross-country terrain, giving Kulhavy the chance to show his mettle.