Steven Ray, aged 36, of Thornbrough Road, Heeley, accepted he stabbed 29-year-old Rory Hemmings in the chest with a steak knife.
Sheffield Crown Court heard Ray had knifed Mr Hemmings, who was dad to girls aged four and eight, during a fight inside Mr Hemmings’ ex-partner’s home on Errington Crescent in Arbourthorne.
“It just happened so quick, like a flash,” Ray, who was in a relationship with Mr Hemmings’ ex-partner, said in a police interview.
The court previously heard that Mr Hemmings had barged into Kirsty Allen’s home at around 8am on Sunday, November 15, accusing her of sleeping with someone else during their 11-year relationship. The court heard Mr Hemmings was told about the alleged infidelity the night before, while drinking.
The jury was told Mr Hemmings was upset about the breakdown of the relationship and the fact he was unable to spend more time with his children.
Shaun Smith QC, for Ray, asked why he stabbed him.
“I was scared that he was going to harm me or Kirsty.”
“Did you have any prior thoughts about harming Rory Hemmings?” Mr Smith QC said. “No, not at all, it wasn’t my intention,” Ray replied.
Before Ray was called to the dock, Detective Sergeant John Dimberline read out a summary of what the defendant had told police.
Ray said Mr Hemmings had sent ‘threatening’ texts to Ms Allen the night before the early morning row.
Ray said: “I woke up in bed alone and heard loads of screaming. Kirsty was screaming, ‘Just get out Rory’. I could hear the girls crying and something like ‘Just go, Daddy’.
“I went downstairs and said, ‘Look at what you’re doing Rory, just go.’
“I just wanted to make him go, I was feeling intimidated and was scared at the time.”
Ray said he threw the first punch as he tried to make him leave.
“It was obvious he wasn’t going anywhere, I tried to push him with my right hand out of the door but couldn’t.”
The court heard the pair started fighting and Ray said he saw Mr Hemmings look at the steak knife on a draining rack in the kitchen.
“I stabbed him. I didn’t mean to stab him, I didn’t mean to hurt him. I just wanted him to leave. It happened so fast, like a flash.”
Ray denies murder.
The trial continues.