Liam Turner admitted wounding Connor Johnson at about 1.30am on January 1 on Charles Street.
Nottingham Crown Court heard yesterday (Wednesday) that Turner bumped into Johnson, who was leaving a friend’s address after a party.
The defendant, of Fairfield Road, said to the victim: “You shouldn’t be hanging around with him, he’s a grass” before punching him.
A fight broke out and Johnson hit Turner in retaliation.
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The defendant left the scene, returning armed with an eight-inch kitchen knife.
He slashed Johnson repeatedly to the face and neck, causing him to bleed heavily.
The police and paramedics were called and Johnson said he feared for his life as he was rushed to hospital. He recalled hearing paramedics seeing how much blood he’d lost and telling the ambulance driver to hurry up.
Prosecutor Gareth Gimson said the victim suffered a four to five centimetre cut to his neck, which was deep and exposed muscle, a three centimetre cut to his right cheek, which caused a flap of skin and a two to three centimetre laceration to his right temple.
The court heard Turner’s previous convictions included assaulting Johnson on Buxton Market Place in 2006.
Guy Mathieson, defending, said his client had had no stability in his life until he met his girlfriend, with whom Turner lived and has a child.
“The problem is that it has not completely extinguished the anger that is inside this young man,” he added.
“He has become devoted to them, overly protective.”
Mr Mathieson told the court Turner wanted to protect his girlfriend, and told Johnson to “back off” or he would stab him, thus giving the victim a chance to run away.
“I’m not saying his actions were justified, proportionate or necessary, but that is why he acted in the way he did,” he added.
Judge Shaun Smith said: “Connor Johnson has recovered physically from these injuries but he still bears the scars.
“I want you to take his victim impact statement with you to prison and read the substantial effect you’ve had on him.
“His life has changed forever. His injuries upset him. He will look like that for the rest of his life. That’s all on your hands.”
Sergeant Darren Pope, who oversaw the investigation, said: “This was a serious assault involving a knife and the consequences could have been far more tragic.
“The victim suffered serious physical injuries but it has also affected him emotionally as he has tried to come to terms with what happened to him.
“I would like to thank the members of the public who witnessed the incident who came forward and were crucial to our investigation.
“The sentence reflects the gravity of the offence and I would urge any person considering carrying a weapon to think again.”