A TAVISTOCK man attacked his neighbour leaving him with a collapsed lung.
Jason Reynolds, aged 47, punched the man after he had called him a name as a row flared over a key.
He changed his plea to admit causing grievous bodily harm without intent on September 13.
Reynolds was due to face a trial at Plymouth Crown Court after initially denying the charge.
A judge adjourned sentence for a probation report but told him he would not be going straight to prison.
Recorder Paul Garlick, who read a psychological report, said any jail term could be suspended with treatment for his problems.
Ali Rafati, for Reynolds, said the defendant’s attack on his neighbour only lasted a few seconds.
He added that he could not have expected his blows to cause such a serious injury.
The court heard that the neighbour had allegedly insulted Reynolds in an argument over a key.
Recorder Garlick released Reynolds on conditional bail until November 7.
He was living with his mother in Launceston and has been barred from entering Tavistock.
Reynolds is also banned from contacting his neighbour – a prohibition which prosecutors want to make long-term under a restraining order.