Brian McKnight fans are planning to boycott his upcoming concert after he called his estranged children, including his cancer-stricken son Niko, "evil" and the "product of sin."

Just days after McKnight posted a video explaining why he doesn't claim his four oldest biological children, it was announced that the "Back At One" singer will have a show at the MotorCity Casino Hotel in Detroit, Michigan, on June 9.

The hotel's official Facebook account shared a poster showing McKnight smiling, along with a link to the Ticketmaster page where fans can buy tickets.

Fans soon flocked to the comments section, but instead of expressing excitement over the show, many declared that they would not be buying tickets and attending McKnight's concert.

RELATED: Brian McKnight Calls Son With Stage 4 Cancer A 'Product Of Sin'; Admits He Stopped Helping Sick Child

"Nah... And I'm a huge fan. Get it together," one person commented, while another said, "We good[,] Brian. Go sing to those kids."

Another fan wrote: "Brian was my favorite male artist since the early ['90s,] but after seeing the way he treats his children[,] he can kick rocks."

"I'd rather be cutting my lawn with toenail clippers," a fourth comment read.

"When I used to work at the [Sound Board], we used to love when he came, it was always a packed house," another user shared. "I'm not so sure it will be one now... Nah buddy, we [are through] with you until you come back to earth."

RELATED: Brian McKnight Slammed For Calling Biological Kids 'Evil' While Publicly Praising Stepchildren Instead

Brian McKnight Concert

(Photo : Facebook/MotorCity Casino Hotel)

One person even called on 50 Cent to snap up tickets to McKnight's show so the venue looks empty during his performance.

"I need someone to buy out all the seats in the front area so he's singing to empty chairs. Come on, 50 Cent. Work your magic," the user wrote, referring to the rapper's claims he bought 200 front-row tickets to a Ja Rule concert amid their beef.

Another fan suggested one method McKnight can use to entice fans to attend his concert.

"Tell him [to] bring his kids and we might come," the Facebook user commented.

But many other fans stood by McKnight and expressed their excitement for his upcoming gigs, which also include performing at the Hitman David Foster and Friends concert in Indonesia on June 15.

"Can't wait to see you in Indonesia," a fan commented under one of McKnight's recent posts.

"I'm so proud of you, Brian," a second fan wrote. "Keep it going, bro."

Another comment read: "Always a fan, Do yourself a favor and please stop responding to the goofiness out there. People run with half a story and think they can judge instead of cleaning up their side of the street."

"Can't wait for you to come back to Jersey! I came to every concert that you had," another wrote.

Brian McKnight
Brian McKnight speaks onstage during Celebrity Fight Night XXV on March 23, 2019 in Phoenix, Arizona.
(Photo : Emma McIntyre/Getty Images)

McKnight faced backlash last month after he claimed during an Instagram Q&A session that he cut off his four oldest biological kids -- Brian Jr., Niko, Briana and Clyde -- because they were "the product of sin."

"In order to live a life that you love, you have to get rid of the evil and the negativity -- even if that evil and negativity is related [to you]," McKnight said in the video.

McKnight's ex-wife Julie, with whom he shares Niko and Brian Jr., fired back by claiming he was throwing a "tantrum."

The singer later alleged, during another Q&A, that he was forced by Julie to stop helping Niko with his cancer battle.

McKnight alleged that his ex did not want people to see him helping his son because it "would go against the strong narrative that's being pushed out there about" him.

In a statement to Page Six, Julie accused McKnight of lying in his video.

"This is, once again, a response to bait myself [and] my family into his false narrative. He is a liar," she alleged.

McKnight also shares son Brian Kainoa Makoa Jr. with his wife Leilani Mendoza.

Mendoza also has a son and daughter from a previous relationship.

Brian McKnight and wife

(Photo : Emma McIntyre/Getty Images for Celebrity Fight Night)