A 46-year-old man was attacked near JD Sports on Buchanan Street at around 6.40pm on Saturday, July 3.
Two men were involved in the assault, but they were accompanied by around six others who did not take part in the attack.
The victim was taken to Glasgow Royal Infirmary with serious, but not life-threatening, injuries.
After the incident, the assailants were seen making their way south on Buchanan Street.
The two suspects are described as white men, both around 25-years-old.
One had a shaved head and was wearing a grey hooded top, blue jeans and white trainers.
The other had short black hair and wore a black jumper with a white stripe down the sleeve, black trousers and white trainers with a black trim.
Detective Constable Paul Campbell, from Greater Glasgow CID, said: “We’re appealing to anyone who was in the Buchanan Street area around the time of the incident on Saturday, who witnessed the assault or has any information on the group of men involved, to please come forward.
“We are also keen to hear from anyone with potential CCTV, dashcam or mobile phone footage of the area from the day in question.”
If you have any information on the incident you can contact Police Scotland on 101, quoting incident number 3020 of July 3.
If you would like to stay anonymous you can contact Crimestoppers on 0800 555 111.