A Sprague man pleaded guilty Thursday in New London Superior Court to strangling his girlfriend at the time and stabbing her with a screwdriver during a prolonged attack in May 2012.

Jon W. Hoffman, 38, will be sentenced March 19 to five years in prison followed by four years of probation. Initially charged with attempted murder and five other serious crimes, he pleaded guilty to second-degree assault, strangulation and interfering with an emergency call. He will be on probation for four years following his release from prison, and Judge Hillary B. Strackbein will issue a standing criminal protective order that prohibits him from having contact with the victim.

Longtime prosecutor Lawrence J. Tytla has said the case is one of the most egregious domestic violence cases he has ever seen.

The victim, who is the mother of Hoffman’s child, said he attacked her at his home at 46 Bushnell Hollow Road after she told him a window had been broken accidentally. She said he stabbed her with a screwdriver, kicked her with steel-toed boots, beat her about the face and head and attempted to strangle her. During the attack, the victim said Hoffman broke a window in her car and kicked and punched her dog.

She was treated for puncture wounds to her head and face and bruises that resulted in both eyes swelling shut. Her nose and jaw were broken and she had strangulation marks around her neck, according to police, who went to the home after receiving numerous reports that a woman bleeding from the head was knocking on doors and asking for help.

Hoffman has been free on a $500,000 real estate bond while his case was pending. He is represented by attorney Donald J. DiFrancesca.