Eminem has made a career out of pushing the envelope with provocative lyrics that test the limits of acceptable speech.
Fans have grown accustomed to this approach, and like other holdovers from the early 2000s such as Family Guy and South Park, the rapper has often been given a pass in situations where other artists would be forced to publicly apologize.
But even some of Em's most ardent defenders might find themselves cringing at a lyric the rapper recorded back in 2009 and wisely decided not to release.
As E! reports, the offensive line unexpectedly appeared in a Reddit post entitled "(SNIPPET) Eminem - Things Get Worse (Rihanna Diss)."
Published on the site on Monday afternoon, the post contains a 7-second audio clip, in which Eminem -- whose real name is Marshall Mathers -- can be heard rapping the following line:
"I'd side with Chris Brown, I'd beat down a b-tch too."
Not much room for interpretation there.
The lyric clearly refers to the shameful 2009 incident in which Brown brutally beat Rihanna, leaving the singer hospitalized.
The snippet seems to be from the recording sessions leading up to the release of Mathers' 2009 album Relapse.
A different version of the verse that wound up on "Things Get Worse," a collaboration with rapper B.O.B.
It's unclear who decided to shelve the lyric, but fortunately, the decision was made to replace the line with something less offensive before the song's release.
The lyrics are particularly shocking in light of the fact that Mathers and Rihanna are longtime professional associates who have collaborated on a number of songs.
This fact was not lost on the many irate music fans who commented on the situation on social media.
"Eminem grown ass really glorifying abuse for a damn song after my fav lend her vocals to numerous songs for him is disgusting," one fan tweeted.
The line was recorded before Em and Rihanna collaborated on such hit singles as "Love the Way You Lie" and "The Monster."
Along with "2009 was a different time" and "someone (possibly Eminem) made the decision not to release the line" that fact is being cited by Eminem apologists eager to absolve the rapper of any blame.
But the fact remains that Brown's savage assault was on Rihanna was one of the most appalling celebrity stories of the past decade, and its place on the list of Things You Just Don't Joke About is carved in stone.
The same can be said for all instances of domestic abuse, regardless of whether or not the victims or perpetrators are famous.
Neither Eminem nor Rihanna has commented on the leak publicly, but unless the audio turns out to be fraudulent, it's clear that the rapper owes his frequent collaborator an apology -- and a large donation to a battered woman's shelter in her name would be a good place to start.