A Napier woman likely died after being tackled during a game of rugby league and hitting her head on the ground, a coroner has ruled.

Katiana Tereta Pakoti Waikato, who was a "comparative newcomer" to the game, died after she was injured in Hastings on August 27 last year.

Waikato, a mother of one, was a member of the Tamatea Women's Rugby League Team. She was playing the Dannevirke Tigers at Percival Sports Park and the tackle that led to her death happened in the second half, coroner Tim Scott said in a ruling issued today.

Nothing suggested her injuries were caused by "illegal or unsporting play".

"It is not totally clear what happened, but as best as I can determine [Waikato] got possession of the ball and then was either tackled and fell backwards or (less likely) stumbled and fell backwards," Scott said.

"She hit the back of her head hard on the ground. She was able to get up, but could not continue playing."

Waikato was able to walk from the field and across the carpark with her partner before she collapsed.

Team manager Evelyn Rapaea, a registered nurse, saw Waikato leave the field and heard her say she had a sore head.

She and others hurried to help Waikato, and an ambulance was called.

However, it was not until Waikato collapsed that Rapaea realised how serious it was.

Waikato was taken to Hawke's Bay Hospital in Hastings, but died about 8.50pm.

"Sadly, rugby league, along with many other commonly engaged-in sporting activities, has a risk factor," Scott said.

"That risk factor manifested itself in the worst possible way here and led to [Waikato's] death."

The medical cause of death, determined by Dr Matthew Bailey, was a subdural haemorrhage, as the result of the rugby league injury.