Asif Rehman, 20, and Adel Ishaq, 19, attacked William McKeeney in Melville Street, Pollokshields, on 15 January.
Mr McKeeney, who was originally from Malin Head, later died at the city’s Victoria Infirmary.
Rehman and Ishaq, who denied the murder charge against them, face mandatory life terms when they are sentenced at a later date.
During the trial at the High Court in Kilmarnock, the jury was told that Mr McKeeney was attacked while making his way home from a nearby pub.
His partner Annemarie Newlands, 48, said she had been watching out for him from a window of the flat they shared in Melville Street.
She told the court that she had seen “two Asian men stamping on something”.
After they left the scene, Ms Newlands said she was able to see a dark shape which she thought was a person.
When she ran outside she realised the dark object was her partner, Mr McKeeney.
She told the court: “He was very battered and the side of his face was all swollen.”
The trial also heard from Ishaq’s friend, 19-year-old Imran Khan.
He said Rehman had warned him during a phone call that they had just “splattered” someone outside his house.
Following Rehman and Ishaq’s convictions, procurator fiscal John Dunn said: “William McKeeney was an innocent man on his way home when he had the misfortune to run into Asif Rehman and Adel Ishaq.
“Minutes later and in a totally brutal and unprovoked attack, he was beaten so viciously and severely that he would never recover. His murder has shocked the local community.
“I hope that today’s verdict will bring some closure for Mr McKeeney’s family, who have had to deal with the effects of this tragic event. I cannot imagine the mental anguish they have suffered because of these men.”