A man told detectives he was in "fits of tears" after finding the body of his partner who had been killed in their bed while he was out, jurors have heard.
Scott Hoyle said he was initially unsure if David Wilson was "dead or alive" when he returned to their home in Southwick, Sunderland, after being attacked himself, and saw him lying with "a lot of blood all over the bed".
Mr Hoyle said he called for help in a state of shock and when paramedics tried and failed to revive his 49-year-old boyfriend, who had been stabbed seven times, he was in "a very bad state".
Prosecutors claim Daniel Johnson, 20, had attacked Mr Hoyle and taken his keys during a violent confrontation outside the flat in the early hours of December 14, 2014.
It is claimed while Mr Hoyle went to the hospital and police station after his mugging ordeal, Johnson used the stolen keys to get into the couple's home,where he murdered Mr Wilson.
Johnson, of Mulberry Gardens, Gateshead, denies murder and is being tried by a jury at Newcastle Crown Court.
After the killing, Mr Hoyle gave video statements to police, which have been played in court to jurors as his evidence.
Mr Hoyle said during his first interview, in September last year, he had left the home he shared with Mr Wilson in the early hours of the morning and sat in McDonalds, where he ate four cheeseburgers, before heading back.
Mr Hoyle said he saw a person outside his flat, which he assumed was a neighbour.
But he added: "As I got upstairs, I realised it wasn't him.
"He went to assault me, grabbed my keys off me. I manoeuvered him aside and ran downstairs.
"He managed to manoeuver me to the floor, where he started to become violent and attack me.
"I was yelling for help. One of the neighbours heard this. I managed to get on my feet and veered around the corner to the back alley."
Mr Hoyle said he was "frogmarched" to a cash point machine by the attacker an added: "He said he had a knife on him, he was going to petrol bomb my house."
Mr Hoyle said he managed to get away from the mugger, was bleeding, and got help from a passing ambulance and was taken home by the police but had no keys to get in as the attack had stolen them.
Mr Hoyle said he went to hospital and then the police station before picking up a spare set of keys and going into the flat he shared with Mr Wilson.
Mr Hoyle said: "The television was still on from the night before, it was paused, still the same episode.
"I went to see David. That's when I witnessed there was something wrong.
"I wasn't sure whether he was dead or alive. I saw there was a lot of blood all over the bed.
"I saw there was something wrong."
Mr Hoyle said his "natural reaction" was to go to the payphone to call for help.
He added: "I ran all the way there, without hesitation. They asked if he was dead or alive. I said I didn't know.
"I asked for an ambulance as soon as possible.
"I went back to the flat in a state of shock. People outside could see I was in a state of shock.
"The paramedic came upstairs. He tried to revive David."
Mr Hoyle said it was at that point he realised Mr Wilson was dead.
He added: "I had to get out of the bedroom. I was in fits of tears. I went downstairs in a very bad state, a very bad way."
The trial continues.