Sam Jaconelli, 36, a care assistant, from Paisley, was giving evidence at the trial of Lee Anderson, 31, who denies murdering Javaid Ali at his store Sunshine Grocers in Green Road, Paisley, on June 15, last year, by stabbing him in the neck with a knife.
Mr Jaconelli told the High Court in Glasgow he was a good friend of 48-year-old Mr Ali and spent on average an hour a day chatting to him in the shop. He also helped out on occasions serving behind the counter. He was asked by prosecutor John Scullion if he knew Anderson or had ever heard Mr Ali speak of him and he replied: "No, never."
Mr Jaconelli was asked if he recognised Anderson, who was sitting in the dock, and said he did not.
Earlier Mr Jaconelli was asked by Mr Scullion: "Did Javaid Ali sell cannabis?" He replied: "He did."
Mr Scullion then asked: "Did he sell it from the shop?" Mr Jaconelli replied: "As far as I'm aware he sold from his van and not from the shop."
Mr Jaconelli was then asked if he bought cannabis from Mr Ali and said: "I did, yes, on a couple of occasions. I'd phone him up and ask and then I'd get him at his shop and he would go to his van and get it. He never actually sold it from the shop."
Mr Ali's injury severed a carotid artery, causing massive blood loss and cardiac arrest. As a result he suffered severe permanent brain damage and died on June 29 last year after his life support was switched off.
The trial, before judge Sean Murphy QC, continues.