When the tide is right, a spit of cockle shells and other ocean detritus rises up out of the Spencer Gulf and forms a unique beach cricket pitch.

And on one weekend every year — weather and schedules permitting — members of the Royal Port Pirie Yacht Club and Whyalla Yacht Club in South Australia sail out to this temporary pitch in the waters between the two cities to stage a very special cricket match.

Each team battles to see who will take home a jar of Vegemite filled with cockle shells laid into a wood plaque, also known as the Cockle Spit Cricket Challenge trophy.

Rules of the game will be familiar to anyone who has played backyard cricket: each batsman faces six balls, with three runs deduced for every wicket, and six or four runs added for hitting the ball into the water.

Playing with a tennis ball, it is hit and run and one hand, one bounce.

There is a scorekeeper and an umpire, as well as the obligatory sausage sizzle and cooler full of drinks set up under a gazebo on the sidelines.

Setting up for the cricket match on the spit. ( Supplied: Kaz Eaton )

This year marks the 20th anniversary of the first Cockle Spit match, but organiser Alan Moore said a drop in member numbers at the yacht clubs had put the competition on hold for several years.

"Years ago Whyalla had a fleet of large yachts that they would just race to Port Pirie as part of their program, and then on the way home we would go out to the spit as a group, play cricket and then they would continue back to Whyalla," he said.

"But numbers dropped at the clubs and it got harder to organise, so they stopped coming."

After a renewed effort to stage the cricket challenge again, the match was resurrected two years ago.

Mr Moore said the high turnout this year had given him hope the Cockle Spit Cricket Challenge would remain a permanent fixture in the future.

"It is really gratifying to have so many people turn out on the day," he said.

'Bowler's wicket' as deliveries skid off uneven surface

The spit is a tough surface to play on, with fielding and running in the mix of soft sand and cockle shells a challenge for most players.

It could be described as a bowler's wicket, with plenty of deliveries skidding off the uneven surface at strange angles after hitting a shell or rock.

This year there were plenty of spectators and supporters of both teams shouting words of encouragement, and the match was a close affair.

After some handy work with the bat and some tight fielding, the Cockle Spit Challenge Trophy was taken home by Port Pirie, who won the match 54-29.

The Port Pirie skyline provides a backdrop for the match in the Spencer Gulf. ( Supplied: Kaz Eaton )

With Whyalla winning last year, the trophy was passed between the two commodores from each club in a simple handover ceremony.

Some members of the Whyalla delegation vowed to come back to the spit next year with renewed focus to reclaim the title.

With about 50 people making the journey to the sandbar this year, Mr Moore said he expected another close contest for the trophy next year.

"Last year went really well and this year was even better, so hopefully we can have it again next year and get more people involved," he said.

The Royal Port Pirie Yacht Club team took home the Cockle Spit trophy in 2016. ( Supplied: Kaz Eaton )

Taking the trophy home

With the cricket over for another year, everyone made their way back to their vessels anchored in the water just off the sandbar.

Some had to wait longer than others to sail home, because during the match the tide had sunk further than expected, leaving their boats stranded on the sand.

It took another few hours before the tide came up enough to allow them to sail home.

Mr Moore said the first priority after arriving back in Port Pirie would be to get the trophy displayed properly on the wall at the yacht club.

"We've left a screw in the wall and we just hung it straight back on there," he said.

"There's no messing about with that."