Samuel Thomas was heading home after a 21st birthday party with workmates in Sydney when he opened the car door of an Uber and fell into the path of a bus.
The 30-year-old Englishman died instantly.
Friend and fellow passenger Stephen Ronning heard "a loud pop" as he turned to tell the driver, Nazrul Islam, to stop, the Downing Centre Local Court heard on Thursday.
Bus driver Robert Haviland testified he felt a bump, heard a "crunch" and thought he'd "run over a tree branch".
Islam has denied seeing or hearing anything until his other two passengers started shouting.
The 31-year-old has pleaded not guilty to negligent driving occasioning death after Mr Thomas was hit at the intersection of Elizabeth and Bathurst streets at 3.11am on June 17 in 2017.
The Englishman had spent the day working at an events company in Surry Hills where he finished about 8pm.
He then travelled to a Strathfield party where he drank beers into the night with Mr Ronning and colleague Greg Hensman.
The trio caught an Uber back to Town Hall in the CBD which was a "midground" from where they'd all head home.
They spoke briefly with Islam before falling quiet and resting, Mr Ronning said on Thursday. There was "no real conversation" or excessive noise.
The Toyota Corolla was stopped at a red light when Mr Ronning - seated in the front passenger seat - heard the left rear door open and the interior light came on.
He turned to see Mr Thomas "in the motion of getting out".
"I just turned over (to Islam) and said 'Stop' because I knew he was getting out of the car and we were moving at the same time.
"I heard a loud pop ... then the car stopped within a second and I hopped out and saw Sam on the road."
According to Mr Ronning's statement Mr Thomas "never said anything".
Footage from a camera on the bus shows Islam's car stopping on its right-hand side at the intersection.
The victim opens the left rear door before both vehicles accelerate and he falls under the wheels of the bus.
In a recorded interview played earlier on Thursday, Islam told police he accelerated when the light went green, but "did not see anything" and "did not hear anything" until the other two passengers said "Hey, hey, hey" loudly.
"I hear them, I brake. The bus has already braked," Islam said, noting he had moved "maybe five metres".
"They opened the door and go out and say 'Oh my god, oh my god' like that."
He turned his hazard lights on, saw the body and called police.
Islam told officers he had been driving on-and-off since 6am the previous day but had taken breaks and slept.
Mr Hensman will give evidence via video link from the UK on Friday at the hearing before magistrate Mary Ryan.