"There's nothing to indicate that Joshua Hardy had actually done anything," Mr Tinney said in opening Zandipour's second trial, after a previous jury had failed to reach a verdict.
Mr Hardy was outside the McDonald's when Mr Bell and Zandipour left and, having lost both his wallet and mobile phone, asked Mr Bell if he could use his.
Mr Bell pushed Mr Hardy, causing him to stagger, but not fall.
With no apparent warning, Zandipour then grabbed Mr Hardy's left hand and slung him head first into the ground, with great force.
Mr Bell threw his cup at Mr Hardy, then Zandipour inflected three "forceful" kicks to his head and neck area.
The kicks caused Mr Hardy's body to swing around and Zandipour then stomped on Mr Hardy's head and neck area.
"He was completely helpless on the ground and at no time did he say or do anything to warrant this continuing attack upon him," Mr Tinney said.
Zandipour and Mr Bell fled with Mr Hardy lying unresponsive and bleeding on the footpath.
Mr Hardy was pronounced dead less than two hours later at 2.10am in hospital.
Zandipour was charged with murder, but pleaded not guilty.
He shook his head after the verdict was read on Monday, as Victorian Supreme Court Justice Karin Emerton thanked the jury for paying close attention to the evidence.
Outside court, Joshua's father David Hardy urged people to think about the consequences of their actions before they engage in violence.
"Unfortunately, in our circumstances, the consequences have been tragic," Mr Hardy said.
"Two young lives have been shattered."
A pre-sentence hearing will be held on June 21.
HOW A SIX-SECOND ATTACK COST A MAN HIS LIFE:
THE LAST HOURS OF JOSHUA HARDY'S LIFE
• University student had been to a valedictory dinner and then a 21st birthday party
• Put in a taxi by his friends about 12.15am on October 18, 2014
• Is "exceedingly drunk" and loses his wallet and mobile phone before going to the McDonald's on St Kilda Road
• Is thrown to the ground, kicked and stomped on by Kyle Zandipour
• Rushed to hospital where he is pronounced dead at 2.10am.
KYLE ZANDIPOUR
• Former ANZ bank worker
• Drinks and plays video games with Matthew Bell in the apartment he shares with his girlfriend
• Goes to McDonald's where he kicks Mr Hardy three times, stomps on him and flees
• Charged with murder
• Pleads not guilty, claiming he felt intimidated because he thought Mr Hardy was on drugs and may be "unpredictable"
• Jury fails to reach a verdict in Zandipour's first trial
• Found guilty of murder following a second trial.
