Paulius Petrasiunas, aged 25, died "within seconds" of being knifed in the chest by 20-year-old Sean Bulle in Heath Town, Wolverhampton, on July 13 last year, Stafford Crown Court was told.
The pair had argued in Flat 64 at Chervil Rise before they stepped outside, where Bulle - nicknamed Switch - attacked him with a "long and wide" knife which had been concealed in a sheath, said Crown prosecutor Timothy Hannam QC.
Paulius, also known as Paulo and Polo, was found dying by a number of witnesses including his girlfriend, who described him as being "slumped over and bleeding heavily", Mr Hannam continued.
Meanwhile Bulle, who denies murder, fled the scene and discarded the blood-stained weapon between a fence and wall in nearby Wednesfield Road.
The knife wound went straight through Paulo's heart and his lungs, into the top of his back, said Mr Hannam.
He told jurors: "Paulo was killed late in the afternoon in the hallway and doorway of the ground-floor of Flat 64, Chervil Rise.
"That is where he and the defendant had been present when he was stabbed through the front of his chest with a long and wide blade.
"It had more or less gone straight through him. He died within seconds.
"It is the prosecution's case, which I understand is not disputed, that the defendant throughout that day had been armed with a large knife concealed in a sheath.
"The prosecution say his death was murder and this defendant, Sean Bulle, who sits in the dock, was responsible for it.
"It is not in dispute in this case that the defendant did kill Paulo with that knife.
"The issue for you is how he came to do so and what was going through his mind when he did it."
Mr Hannam said the knife could be described as a "machete" or a "Rambo style blade".
The argument between the pair started after Paulo took a call from someone called Shanky, which Bulle did not like him doing, jurors were told.
Paulo and Bulle then travelled to collect an "important bag" from an Asda car park, which they later dropped off at Flat 19, Lincoln Street, in Heath Town.
After that, they went to Flat 64 at Chervil Rise, which was on the ground floor of the four-storey block, where they "argued after they got inside and the defendant was angry", said Mr Hannam.
He said: "[Paulo's girlfriend] said Paolo was upset and angry when they got back.
"The defendant appeared in the doorway of the living room and said 'come'. In response to that, he walked out and closed the door behind him.
"She heard Paulo say 'if you are going to stab me, then stab me' and then heard a scuffle and heavy breathing.
"Paolo was outside on the floor, his knees were pulled up to his chest, he was slumped over and bleeding heavily. His body was found lying outside the front door. There was no sign of the defendant."
When police and ambulance crews arrived, they were met with a "chaotic and emotional" scene, said Mr Hannam.
Paulo was pronounced dead at 5.48pm that day, a Monday, despite the best efforts of the emergency services.
In the time following the attack, Bulle allegedly made his way across Wednesfield Road, which is the main road going through Heath Town, in the direction of Tumbler Grove.
One eyewitness reported seeing Bulle holding a machete and struggling to carry it because was "so large", the court heard.
Mr Hannam said Bulle was moving in a "calm and calculated manner" and had slowed down from the "dreadful scene" - despite "what he had done to his friend".
Bulle allegedly disposed of the knife in a "void space" between a fence and wall, which was strewn with rubbish.
It was later recovered and DNA analysis showed the blood on that weapon was the same belonging to Paulo.
Paulo lived nearby in Lincoln Street and was originally from Lithuania.
Sean Bulle, 20, of Clover Ley, Heath Town, denies one count of murder.
The trial continues.