Eminem has issued an apology to his <em>Love the Way You Lie</em> collaborator Rihanna in a newly released song from his surprise album. The US rapper, who unexpectedly unveiled <em>Music to be Murdered By Side B </em>on Friday, gave a shout-out to the singer in the track <em>Zeus</em>. "But, me, long as I re-promise to be honest / And wholeheartedly, apologies, Rihanna," Eminem, born Marshall Mathers, raps. "For that song that leaked, I'm sorry, Ri / It wasn't meant to cause you grief. Regardless, it was wrong of me." The musician, 48, is referring to an unreleased track leaked in 2019, in which he backed US singer Chris Brown, who assaulted Rihanna in 2009. In the untitled track, Eminem said: "Of course I side with Chris Brown." Brown, 31, faced a felony conviction in 2009 for assaulting then-girlfriend Rihanna, 32. He was sentenced to six months of community service, five years’ probation and a year of domestic violence counselling. At the time the song was leaked, Eminem revealed it had been recorded years before and was not intended for release. "This is a leak of something that's over 10 years old," a spokesperson for the musician said last year. "After Eminem recorded it, he scrapped it, and rewrote it." Eminem and Rihanna have collaborated several times, including on <em>Numb</em> on her 2012 album <em>Unapologetic</em> and <em>The Monster</em> from <em>The Marshall Mathers LP 2</em> in 2013. Rihanna has not yes publicly responded to the lyrics featured in Zeus. <em>Music to be Murdered By Side B</em>, which accompanies Eminem's January album <em>Music to be Murdered By</em>, features appearances from DJ Premier, Ty Dolla $ign and Sly Pyper.