Two doctors say the baby's injuries at the centre of a Dunedin assault trial, could only have been caused by force

A high-profile sportsman is accused of causing 13 rib fractures to an infant in July 2023.

The Crown alleges force was responsible, while the defence argues underlying bone fragility.

Professor Ben Wheeler told the court his review showed nothing wrong with the infant's bones.

He says a mild vitamin D deficiency was found, but stressed this didn't increase fracture risk.

Forensic pathologist Leslie Anderson says the injuries couldn't be explained by routine handling or physiotherapy.