Unfavourable conditions have forced organisers to call a lay day at the Billabong Pro in Mundaka, northern Spain.

Only 45 heats in nine days have been held at the Billabong Pro - an average of just five a day - due to the tricky tidal changes which can transform raging barrels into a lake in a matter of hours.

Competition is still only in the third round with just three days of competition left.

Three third round heats are still to be contested including an all-Australian Mick Lowe-Dean Morrison showdown.

Runaway series leader Kelly Slater can win an unprecedented eighth world title with victory at Mundaka.

He has already won through to the fourth round along with nearest title threats Taj Burrow, Mick Fanning and Joel Parkinson of Australia and three-time world champion Andy Irons.

Organisers will check conditions on Friday morning.

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