Waterproof paper was used to print the maps on and, while the paper remained dry in the morning rain, the ink rubbed off in the wet, event co-ordinator Warwick Williams said.

"We haven't got the right paper-ink combination," he said.

"The waterproof paper was fine when it was dry but not when it's wet _ the ink rubs off."

Competitors usually hold a compass with their thumb on top of the map as they run, and in the wet the compass was rubbing the ink away.

One runner lost a "critical" part of his map _ as in the part he was on _ and had to follow another competitor until he returned to a remaining part of his map.

Williams said the event would return to using "old-fashioned" paper maps for the final leg of the event to be held at the University of Ballarat today.

Australian No.1 Julian Dent had no such problems, however, and stormed to his fourth straight victory, this time by over eight minutes.

The win guarantees Dent overall honours, which are taken from the competitor's best four results.

Kathryn Ewels, Australia's second-ranked woman, made it two from two, but cannot win overall as she missed the first two events.

Susanne Casanova, ranked fifth, should claim the overall prize, although her fellow South Australian Vanessa Round is still an outside chance.

In the second-tier course, former Ballarat resident Ian Lawford finished second and is top of the table, while his mother Jenny Bourne crossed the line first to set up an intriguing final day battle with her daughter Belinda Lawford.

Belinda finished second, but holds a four-point lead going into the final day.