Malcolm Barnard launched his assault during a scuffle with Thomas Powell at the Blue Boar pub in Ludlow, leaving his victim with multiple cuts to his face and around his left eye.
Footage from CCTV cameras at the pub in Mill Street showed Barnard, 33, striking Mr Powell with a glass, despite his victim trying to move away from him.
Barnard was jailed for four years and nine months when he appeared at Shrewsbury Crown Court yesterday, having admitted a charge of inflicting grievous bodily harm with intent following the attack in April last year.
Barnard, formerly of Honey Meadow, and now of Rocks Green Crescent in Ludlow, was also banned from the Blue Boar for two years.
He had initially denied a charge of wounding with intent and was due to face trial, but changed his plea to guilty.
Judge Robin Onions said that while Mr Powell's injuries were unpleasant they were not serious, although he had suffered some long term effects.
"This was an offence committed in the heat of the moment and while under the influence of alcohol. It was a single blow committed in anger," he said.
Judge Onions said he accepted the sentence would hit the defendant and his family hard.
"But there is a lesson to be learnt here that people who use a weapon in the way you did will lose their liberty, regardless of personal or family circumstances," he said.
At an earlier hearing Mr Kevin Grego, prosecuting, said that Mr Powell and his brother knew the defendant from attending a local gymnasium.
He said Barnard was seen talking to people at the pub and there was an exchange between him and the victim.
Mr Grego said the CCTV footage showed the victim being stuck in a confined space during the confrontation before he was struck with a deliberate blow to his face.
He said that the footage showed Barnard moving away and showing no interest in Mr Powell – either to continue the assault or to offer him help.
The court heard yesterday that Barnard was shocked by the CCTV footage as he remembered the fight, but not hitting Mr Powell in the face with the glass and was "absolutely gutted and ashamed of what he saw".
Mr Powell required stitches around his left eye and to his cheek, but there were no long standing eye problems.
Mrs Debra White, for Barnard, said her client had voluntarily undergone anger management counselling since the incident.
She said that Barnard had lost work and had recently lost his home due to financial difficulties.