Bach Leaves Skid Mark on Rap Song

9/4/2007 10:56 AM PDT
In a classic, "Who the hell expected these two people to hang out?!" moment, former Skid Row frontman Sebastian Bach and gangsta rap legend Kurupt came together in front of TMZ cameras -- to bust a rhyme!

Bach and Kurupt kicked out a flow in front of the Rainbow Room yesterday, where the sleeveless metal-head gave an impromptu performance of the LL Cool J classic, "Mama Said Knock You Out" -- the same hit he rocked out the night before on MTV's "Celebrity Rap Superstar" -- while the rapper and manager David Weintraub gazed on in amazement.

Don't call it a comeback ...