Ricky John Izard, 28, appeared in the Launceston Supreme Court before Justice Robert Pearce on Tuesday.

Izard had previously pleaded not guilty to murder, but on Tuesday entered guilty pleas to the charges of manslaughter, aggravated burglary and perverting the course of justice.

The court heard Izard was armed with a screwdriver when he and co-accused Mark Rodney Jones trespassed at a Newnham property on January 1 with the intention of assaulting Mr Breward, but the victim died during the assault.

The Mowbray man was reported missing in January 2017 after not being seen since New Year's Eve.

Weeks after the missing person report was filed, Mr Breward's body was found by divers at Lake Eugenana, about 10 kilometres south-west of Devonport, in February 2017.

Between January 1 and February 3, 2017, Izard disposed of the victim's body and provided false information to police investigating the disappearance of 22-year-old Mr Breward.

The court heard facts and sentence for Izard would be delayed until his Mr Jones' trial was complete.

Izard was remanded to reappear in the Supreme Court on July 1.

Mr Jones, of West Launceston, has pleaded not guilty to murdering Mr Breward.

He will appear for trial in the Launceston Supreme Court on June 17.