Strathclyde Police are appealing for information after the man was assaulted in Cardonald at around 10pm on Saturday. The 53-year-old victim was attacked by a man as he was walking along Paisley Road West near to Berryknowes Road.
He had left a pub and was walking to catch a bus home when he was attacked and repeatedly punched for no apparent reason. He suffered serious facial injuries and was taken by ambulance to the Southern General Hospital in Govan , where his condition is stable.
DC Carolanne Montgomery, of Pollok CID, said: "The injured man was attacked and punched several times by the suspect for what would appear to be no apparent reason.
"His injuries will leave a permanent scar. The suspect ran off towards Lammermoore Avenue."
He is described as white, Scottish, 45 to 49, 5 ft 7 in tall of medium to stocky build, very short, shaven hair and balding. He was wearing a light coloured top and jeans.
Anyone with information can contact Pollok CID on 0141 532 5600 or Crimestoppers on 0800 555 111.