An intruder picked the wrong Auckland house to burgle when he was caught in the act and dealt a beating by a kickboxer and martial arts expert living there.
Brook McRae, 23, delivered the blows after chasing two men through his father's Mt Roskill home in the early hours of Sunday.
Mr McRae said he did some boxing training while at Auckland Grammar School then went on to study the martial art form ninjitsu.
He also took up kickboxing three years ago.
"I'd just done it as a sport until [the break-in]," he said yesterday.
Mr McRae said he heard noises in the six-bedroom house but thought it was his younger brother returning after a night on the town.
About an hour later he was woken by two men when they walked into a bedroom where he and his girlfriend were sleeping.
The men ran from the bedroom throwing aside electrical equipment they were carrying, knocking over chairs and smashing bottles as they tried to find a way out.
The pair clambered up a 2.1m wall but Mr McRae managed to grab one man and they struggled to the ground.
"He got one punch on me and then I started giving it back to him and chucked him into a brick wall."
He knocked the burglar unconscious and dragged him back upstairs and put him in a headlock as he phoned police.
Mr McRae said the man came around while he was on the phone and started punching him again.
"As he was punching me in the side he was saying, 'Nah, it's all sweet bro, I'm telling you it's all sweet'."
An infuriated Mr McRae started punching back, telling the man it was not "sweet".
Police arrived within a few minutes and arrested the man.
Mr McRae still has the hat of the second intruder and said he would hand it over to police - unless the man wanted to stop by and pick it up.