Officers were on Union Street due to a different matter, when Patrick Gillies punched Michael McCafferty in the face.
In response, McCafferty threw a can of liquid at Gillies.
At 10.20pm, McCafferty was spotted by members of the public walking outside the Rennie MacIntosh Hotel with a bottle in his right hand.
Police approached and asked for his details. He said: “I am not a grass, sorry.”
McCafferty was taken to a police van and became extremely abusive towards officers. He shouted: “I will slit your throat”. He was arrested.
READ NEXT: Man attacked Glasgow KFC staff and customer after being woken up
Both men appeared at Glasgow Sheriff Court but the procurator fiscal depute did not reveal the circumstances of Gillies’ arrest.
They pleaded guilty to fighting and conducting themselves in a disorderly manner.
McCafferty also admitted to having an offensive weapon – a glass bottle-, striking officers with it, uttering threats and resisting arrest.
McAffery’s lawyer said: “He is 32. There were substances involved, it will not come as a surprise.
“He was initially assaulted and he stupidly retaliated. He has very limited memory. He accepts his conduct. He is entirely embarrassed.
“He knows he should have walked away and called the police.
“Since then, he has attended the Crisis Centre. He looks a lot better. He is well-spoken. He has done a lot of work.”
Meanwhile, Gillies’ solicitor said: “He does struggle to remember what happened. He was under the influence of alcohol and drugs.
“He does not wish to use this as an excuse and he is very remorseful.
“He does have previous convictions. He is 37 years old and struggles with homelessness.
“There is stable accommodation for him now, outside the city centre.”
Sheriff Jonathan Guy sentenced McCafferty, of Dennistoun, to two years of supervision with a requirement to engage with addiction services.
He was also tagged for 81 days, forcing him to stay at home between 8pm and 8am each day.
Gillies, of Baillieston, was sentenced to eight months of supervision.
