A horse and his rider had a lucky escape at Auckland's last race meeting of the season when a six-metre-deep hole opened up underneath them, sending the pair tumbling down the track.

Jockey Rogan Norvall escaped serious injury when he was sent flying from seven-year-old gelding Buckles in the seventh race at Ellerslie racecourse on Saturday.

The fall was caused by a six-metre deep hole which gave way on track, catching Buckles and his ride at the 400m mark.

Norvall landed on his head when he was flung from the horse but suffered only superficial injuries.

Buckles also came out of the fall unscathed.

"The horse has put his foot in the certain place and the ground just subsided," Auckland Racing Club chief executive Cameron George said.

"It was a fairly big hole in the end because it just started giving way to what appears to be an old down pipe of some nature.

"The jockey and horse are OK and that's the most important thing for us."

Stewards called off the last race at the meeting, the final day of racing at Ellerslie for the 2012/13 season.

"There's just no room for discretion with those issues, as soon as I saw the hole I said `call the last race off,' I'm not taking the punt," George said.

"I couldn't see the bottom of it, it is bloody deep."

ARC says it doesn't know exactly what caused the hole but is taking the matter very seriously.

Engineers will be on track first thing on Monday morning to assess the hole and surrounding areas.

"We just never ever jeopardise safety of a jockey or a horse," George said.

George said the club would make a call on what repair work needs to be done once the team of engineers had assessed the track.

"It's certainly not a matter of just filling the hole," he said.