A 25-year-old Baton Rouge woman is awaiting sentencing in September following her conviction in the stabbing death of her boyfriend at his GSRI Road apartment last year.

Hysom Blunt, 26, was stabbed in the chest on March 23, 2010, during what authorities said was an argument with his live-in girlfriend, Monchelle Austin.

State District Judge Don Johnson found Austin guilty of manslaughter Friday.

Manslaughter carries up to 40 years in prison.

Prosecutor Will Morris said the judge will sentence Austin on Sept. 19.

Austin’s attorney, Philip House, said Monday that Blunt and Austin had a “five-year tumultuous relationship’’ and Blunt’s blood-alcohol content was above the legal limit at the time of his death.

“She was defending herself,’’ House said of Austin.

Austin told East Baton Rouge Parish sheriff’s deputies she stabbed Blunt with a knife during an argument that escalated to a physical altercation.

The argument started because Austin would not let Blunt sleep in their bed, an affidavit of probable cause says.

During the fight, Austin grabbed a knife but was disarmed by Blunt, who told her to be careful because “she was going to cut herself,” the affidavit states.

Austin was accused of grabbing another knife and stabbing Blunt in the chest just before 1:30 a.m.

Deputies, responding to a 911 call from Austin, found Blunt lying outside on the ground in front of the apartment, sheriff’s officials said at the time.

Blunt was taken to a local hospital where he was pronounced dead.