Shane Mayer, from Wolverhampton, died three days after he was stabbed multiple times by 20-year-old Ramani Sanderson in Darlaston in July 2019.
Sanderson was convicted of murder at Birmingham Crown Court on Wednesday.
Fellow defendants Joseph Till, 21, and Kamron Reid, 20, were found not guilty of murder but convicted of manslaughter. Lewis Green, 21, was cleared of murder and walked free from court.
All four men had pleaded not guilty to murder ahead of the trial. Although Sanderson carried out the stabbing, the other three defendants were jointly charged with murder, with their involvement alleged to be joint enterprise.
Sanderson repeatedly stabbed Shane with a foot-long blade outside Gabba's Bar, the old Herbert's Park Tavern in Forge Road, just after 11pm on July 24.
Sanderson was one of four hooded men who Shane was set upon in the wake of two earlier confrontations at the pub that night, one of which involved Shane's friend.
Having been stabbed, Shane managed to run away to a shop where he collapsed and was was found by a member of the public. He was taken to hospital but never regained consciousness and his life support machine was turned off three days later.
Michael Burrows QC, prosecuting at Birmingham Crown Court, alleged all four defendants "shared the intention to kill or seriously injure," Mr Mayer.
However only Sanderson was found guilty of murder by jurors who reached unanimous verdicts after deliberating since last Tuesday.
Sanderson was also found guilty of wounding with intent in relation to an unrelated attack on a taxi driver less than three months earlier.
That attack saw him strike the driver on the head with a knife outside the Bradford Arms pub in Walsall on April 29, 2019.
Sanderson had pleaded guilty to possessing a bladed article in relation to the taxi driver attack but had denied wounding with intent.
He admitted possessing a bladed article in relation to the attack on Shane partway through the trial.
Meanwhile Green, of Heathfield Lane West, Darlaston, had pleaded guilty to possessing an offensive weapon after carrying a hammer during one of the confrontations that preceded the fatal attack on Shane.
Miss Rebecca Wade, defending Green, said: "He is a man who is not criminally-minded, his family are a normal working class family from Darlaston.
"At the start of the evening of July 24 none of them could have predicted how the night tragically ended. By the jury's verdict he played no role in the death of Shane Mayer.
"What took place that night was wholly out of character for him. He had his hopes dashed of joining the army for medical reasons but is not shy of work."
Judge Simon Drew handed Green three months in custody, but he had already spent almost a year on remand so was released on Wednesday.
Sanderson, of Walsham Road, near Peckham, London; Reid, of Herberts Park Road, Bloxwich and Till, of Summer Street, Willenhall will be sentenced at a later date.