Shirtless in a police interview room, a man denied murdering his ex-girlfriend’s jealous lover while expressing indifference at the man’s violent demise.

Jealousy and animosity have been put forward as possible motives as a jury trial in the NSW Supreme Court continues.

On Tuesday, a recorded police interview conducted with Dunbar the day after the alleged murder was played to jurors.

“To be honest I don’t care he’s dead – he’s a piece of shit,” he told interviewing officers at Mount Druitt police station.

“No way did I put a piece of stick or any sharp object in him. No way in the world, I’m not a murderer.”

Naylor was dating Dunbar’s former partner Erin Rogers when he was stabbed in the heart with a box cutter.

Jurors have previously heard that the 59-year-old was jealous of Naylor’s relationship with his ex-girlfriend.

This animosity allegedly increased when Naylor stole his $270 silver and gold eagle ring, jurors were told.

During the interview, which was played to the jury, Dunbar sat shirtless with both hands bandaged heavily.

He told police that Naylor had also stolen his wallet and bank card.

He said he had initially walked away from the much larger, stronger man when the ring was stolen because he had to “pick his targets”.

“(Mr Naylor) just stands over weak people,” he told officers in the interview.

“He’s a bully. He was a bully, sorry.”

Dunbar then says he soon returned to confront Naylor and get the ring back.

He appeared to get emotional telling police he was king-hit twice before a larger neighbour punched the 45-year-old in the head.

Dunbar then claims he was “slashed” by Naylor with a box cutter.

He said he fled down the street, grabbed a lump of wood for self-defence, and hid under a car and then in a nearby empty house.

When asked to describe the neighbour, he said he was an Australian who was not solid and not fat.

He said in the interview he could not remember what the man was wearing or what his hair colour was, however.

After being told he had been seen washing his hands under a garden hose, Dunbar said he had been trying to get rid of some grease after hiding underneath the vehicle.

Rogers told police that her former partner had gone to a toolbox in the lounge-room to retrieve a box cutter still in its wrapping prior to the alleged murder, the jury heard.

The trial continues on Thursday.