Christopher Bjerkness didn’t explain his predilection for slashing exercise balls with a knife, but he told the sentencing judge he understands he will probably be sent to prison if he ever again carries out his weird fetish.

Bjerkness, 34, of Duluth was sentenced in St. Louis County District Court on Wednesday to 23 months in prison, but the sentence was stayed for four years of supervised probation. During that time he will receive treatment while living in a group home for people with traumatic brain injuries.

The defendant, who developed a reputation as the “Ball Slasher” because of several such incidents, earlier pleaded guilty to third-degree burglary for breaking into the Chester Creek Academy fitness center in May. A staff member for the school, operated by Northwood Children’s Services, told police that Bjerkness was found in the play therapy room. An investigating officer observed several large exercise balls in the area where Bjerkness had been.

Bjerkness was convicted of the same crime in 2009 when he admitted breaking into the SMDC-Duluth Clinic West building and slashing balls there. In 2005, he was convicted of first-degree criminal damage to property after making an unauthorized entry into the Sports and Health Center at the University of Minnesota Duluth on several occasions between February and September 2004. He admitted to using a knife to slash about 72 exercise balls during three incidents at the college. The different-sized balls were valued at $30 to $60 each.

Judge Mark Munger asked Bjerkness if he had any comment before being sentenced.

“No, your honor,” the defendant said.

Munger followed the recommendation of Arrowhead Regional Corrections probation officer John Kantonen, which was supported by St. Louis County prosecutor Leslie Beiers and public defender Laura Zimm, and gave Bjerkness probation rather than a nearly two-year prison sentence.

Munger told the defendant that he considered him to be vulnerable and didn’t want to send him to prison. “This is probably your last chance to get this taken care of and turn your life around. Understood?” Munger asked Bjerkness.

“Understood,” the defendant answered, nodding his head affirmatively.

He will be released from the St. Louis County Jail today and transported to the group home. He spent 249 days in jail.

Bjerkness told the News Tribune in a 2009 interview that he couldn’t explain his fetish. He said he suffered from fetal alcohol syndrome, bipolar depression and cerebral palsy. That information was confirmed by his adoptive parents.

As conditions of his supervised probation, Bjerkness will be placed in a group home for people with traumatic brain injury approved by Arrowhead Regional Corrections and St. Louis County Social Services. He must complete counseling as directed. He’s ordered to stay off Northwood Children’s Services property, abstain from the use of alcohol and drugs, unless prescribed, and submit to random testing.

Beiers said part of Bjerkness’ treatment is being paid for by St. Louis County Social Services.

“I think the state is concerned with protecting the public safety, obviously,” she said outside the courtroom after the hearing. “In this case, the best way to do that is by combining a consequence and appropriate treatment. If he’s not able to comply with treatment and make some progress, the state at some point will be in the position of having to ask that he go to prison. And we hope that we don’t have to do that.”