A teacher punched a pupil in the face for saying he had a 'moustache like a paedophile'.
The 13-year-old boy teased the adult when he came off the field after a game of school touch rugby in New Zealand.
He asked the student 'if he wanted a smack', prompting the lad to point to his cheek and say 'yes, right here'.
The teacher, who cannot be named for legal reasons, then punched the youngster's right cheek and said 'you're not laughing now'.
A Teachers Disciplinary Tribunal into his behaviour heard he had been 'play fighting' with the pupil in the run up to the game.
At one point, he lightly kicked the boy on the bottom, according to the New Zealand Herald.
He said the boy was frustrating him and blamed the attack in February 2018 on the drug Lorazepam.
He was taking the medication to help him deal with anxiety.
The tribunal said: "In explanation, the respondent said he was frustrated that the student had continued to give him cheek about his moustache and it was upsetting to him as a male teacher to be called a paedophile.
"He suggests that his response of punching the student was a 'paradoxical reaction' to being prescribed Lorazepam on January 24, 2018, which was medication he is prescribed for stress."
He wrote a letter apologising to the pupil but could not hand it over because the student did not want to take part in the 'restorative process'.
The tribunal found the assault amounted to 'serious misconduct', although it decided to pursue a 'rehabilitative approach'.
He was told he must have a mentor for a year and disclose the tribunal's decision to any future employer for the next two years.
The teacher was also ordered to pay £1704.89 in costs.
He was initially charged with assault by police, however the prosecution was dropped after a resolution was found.
