The victim of a knife attack in Hamilton needed 14 stitches in a wound to his face.
Mark McGowan, of Cambuslang, claimed it was an act of revenge after he had been slashed.
McGowan, 35, appeared at Hamilton Sheriff Court on Friday.
He admitted assaulting a man to his severe injury and permanent disfigurement at Burnbank Centre on June 5 last year.
Aga Mathieson, prosecuting, said McGowan approached the victim at about 5.30pm and tried to start a fight.
She told the court: “He removed a large knife from his pocket, lunged towards the victim and slashed his face.
“McGowan then discarded the knife and fled. Police were contacted and the incident was captured on CCTV.
“The victim had a 10cm wound above his eyebrow that required 14 stitches and has left a scar.”
The court heard McGowan told a police officer: “It was retaliation, mate. He stabbed me on the face on Saturday.
“Am I supposed to let them get away with it?
“I haven’t slept since they attacked me. I didn’t want to kill anyone. I just wanted to hurt him.
“I can’t help myself – I have bipolar. I should have listened to my mum and stayed in the house.”
Defence lawyer Andy Iles said his client had been chased and attacked by the victim and another man after refusing to give them alcohol he’d bought.
Mr Iles stated: “He has a very unstable personality and found it difficult to cope with this intimidation.
“He took the action he did in the hope that it would stop.”
Sheriff Michael Higgins deferred sentence on McGowan, of Clyde Place, until next month for background reports.
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