Around 8.20pm a 56-year-old-man was returning home when he noticed a male youth within a rear garden of Ayr Street.
The man challenged the suspect about being in the garden, which prompted him to come out onto Adamswell Street and subject the man to an unprovoked attack.
The suspect made off on a mountain bike onto Springburn Road, accompanied by two male youths, who had been loitering near to the entrance of the residential car park prior to the incident.
Emergency services attended and the victim was taken to the Glasgow Royal Infirmary for treatment to a serious facial injury.
The suspect is described as being six feet tall, large build, and at the time was wearing a black balaclava which covered his face, a black skip hat and dark clothing.
The two male youths in the company of the suspect are described as white Scottish, aged between 12 to 15 years old and around 4ft 10 in height. Both were also in possession of mountain bikes.
The first youth had red hair and was wearing a red-t-shirt. The second had blond hair and was wearing a green zip top.
Detective Constable Andrew Barbour said: “The victim was assaulted after challenging the youth who was loitering in a garden where he did not belong.
“This type of violent behaviour is unacceptable and officers are currently carrying out door to door enquiries and checking CCTV in order to trace the individual responsible.
“I am appealing to anyone who was in this area around the time of the incident and may have noticed male youths making off on mountain bikes, or hanging around beforehand, to please get in touch.
“I would also urge the two male youths who were in the company of the suspect to come forward and assist with our investigation.
“Anyone with Information is asked to contact Maryhill CID via 101, quoting reference number 3698 of 26 of September 2018. Alternatively, please call Crimestoppers on 0800 555 111, where anonymity can be maintained.”