A day after Chris Brown trashed a TV dressing room following questions on his 2009 attack on Rihanna, PR expert Mike Paul said the once-popular singer is making it difficult for fans to get back on his side.

Brown needs to get comfortable with his past and say sorry if he's ever going to rehabilitate his image, Paul -- known as "The Reputation Doctor" -- told CTV's Canada AM on Wednesday.

Brown, 21, threw a chair through a window Tuesday after Good Morning America co-host Robin Roberts asked him about the assault – despite reportedly approving the question in advance, according to TMZ.

An unnamed source told The New York Daily News that the R&B singer completed his scheduled performance before flying off the handle.

"He looked like he wanted to kill somebody. He went completely nuts," the source said.

Brown then stormed out of the studio and took part in a street-court basketball game. He was photographed outside without a shirt on, and witnesses reported hearing heckling from the sidelines.

He was photographed smiling outside an art gallery just hours later.

ABC has decided not to pursue charges, a decision that works to Brown's benefit as he continues to serve probation following his assault conviction. He has undergone anger management and domestic abuse counselling since the assault, which happened two years ago as the then-couple was on their way to the Grammy Awards.

Pop singer Rihanna is still protected by a restraining order that prevents Brown from coming closer to her than 10 feet.

While the album he released months after his arrest tanked, he had appeared to be working to rehabilitate his image while promoting his latest release, "F.A.M.E."

During Tuesday's interview, Brown looked visibly agitated as he responded to Roberts' question.

"It's not really a big deal to me as far as that situation," he said, pressing the interviewer to focus on his music. "I mean, I'm past that in my life… Go get that album."

Afterward, Brown posted a Twitter update saying he was "tired" of people who weren't his fans.

Mike Paul, president of the MGP and Associates public relations firm, said the singer's attempts to shrug off Tuesday's blow-up have taken his tarnished image from bad to worse.

"If I were counselling him, one of the things I'd say is you must be sure to own this issue," said Paul, speaking by video link from New York. "This is the biggest thing that's ever happened in your life. What do you mean, ‘It's not a big deal?' You don't get to choose what others think."

If Brown were his client, Paul said he would encourage him to offer a sincere apology, and use his past to generate discussion around the subject of domestic assault. As it stands, he's likely avoiding taking responsibility on advice from his legal team, Paul said.

"That's a huge mistake," he said, noting Brown declined an offer to return to the show the following day. "Attorneys are not experts in the court of public opinion and dealing with crisis PR. I think they're believing this is something that's going to be pushed under the rug.

"That's a lie from the pit of Hell, that there's no such thing as bad press... He's got a long road (ahead)."