A police detective pushed his wife to the ground at their home and caused injuries to her head, hand and shoulder, a court heard.
Det Con David Alway, 41, denies an assault causing actual body harm to Tamsyn Alway in Bournemouth on 13 December 2019.
A friend of Mrs Alway, Simon Storr, said they were on a video call when her husband returned home from a night out.
He told Southampton Crown Court a row then erupted between the couple.
Mr Storr said he organised an Uber taxi to pick up Mrs Alway, who was "very distressed" when she arrived at his home.
He added she had a "large lump on her head", which she said happened after being pushed into the garden.
Det Con Alway, of Dorset Police, is also accused of causing an injury to her hand and shoulder.
Sheelagh Rogers, Mrs Alway's mother, said in a statement the couple of 10 years had ended their marriage in June 2019, but remained living in separate bedrooms as neither could afford to move house.
Det Sgt Mark Portelli, Det Con Alway's line manager, said the defendant told him he had pushed his wife and she hurt her wrist falling to the ground.
He was arrested shortly afterwards.
In his police statement read to the court, Det Con Alway said: "I pushed Tamsyn in self defence.
"She was standing directly in front of me, shouting and screaming at me, saying she hated me.
"She previously assaulted me four or five months ago, she punched me in the face. At that time it was very similar circumstances."
He added: "I pushed her with two hands with no intention of hurting her, to get her away from me."
A Dorset Police spokesman said the defendant is on restricted duties.
The trial continues.