A man on Thursday admitted that he killed a Slidell optometrist while mugging him in the French Quarter back in 2011.

Bobby J. Troy Jr., 23, pleaded guilty to manslaughter in the death of Dr. Brent Hachfeld, 37, a native of Minnesota who had a practice at the Wal-Mart on Natchez Drive in Slidell. He was sentenced to 35 years in prison, with credit for time served since his arrest almost four years ago.

Troy, who was originally accused of second-degree murder and would’ve received a mandatory life sentence if convicted of that crime at a trial, also pleaded guilty to obstruction of justice as part of a deal that resolved several other charges he drew as well while awaiting trial in Orleans Parish Prison.

Those charges included attempted second-degree murder, second-degree battery, battery of a jail guard and contraband violations.

When he was killed Oct. 16, 2011, Hachfeld was attending a friend’s bachelor party on Bourbon Street, and he meant to spend the night at a relative’s condominium nearby, his family said after his slaying.

But, before getting to the condo for the night, he was struck in the back of his head and robbed in the 900 block of Dauphine Street. He was taken to the hospital after being found in a pool during the early morning hours, and he died there.

Hachfeld left behind a wife and a daughter who was about 2 years old at the time.

DNA evidence led the New Orleans Police Department to identify Troy as the prime suspect in Hachfeld’s slaying a couple of weeks later. Troy soon left for a town in Missouri by bus but was captured within a few days and eventually extradited to New Orleans.

Hachfeld’s relatives said one of the last things he did before embarking on his ill-fated trip to the French Quarter was to finalize plans for a Disney World vacation with his wife and daughter.

It would’ve been their first vacation as a family, Hachfeld’s relatives said.