Two men forced their way into a Hove flat, attacked the man who lived there and stole £600 cash last night.
The 32-year-old victim was hit about the head with what was described as a metal bat of some sort.
He was treated for head injuries at the Royal Sussex County Hospital and kept in overnight.
The burglary happened in Clarendon Road, Hove, just before midnight.
The two men knocked at the door and when the victim answered they forced their way in.
One of the burglars was described as a 5ft 3in tall bald black man, of medium build and in his mid twenties.
He was wearing a black jacket with dark coloured jeans and trainers and possibly gloves too.
The second man was described as slightly taller. He was also wearing all dark clothing and had his face covered with a dark scarf.
Detective Sergeant Helen Paine asked anyone with information to call Sussex Police on 0845 6070999 or the independent charity Crimestoppers anonymously on 0800 555111.