Although Jay-Z has insinuated that he's going to verbally assail his nemesis Nas again in the future, on tracks leaked from the Best of Both Worlds album, it's Jay's partner on the project, R. Kelly, who lays into a musical adversary.

On a track labeled "Hold Up" that infuses handclaps and guitars on the beat, Kelly throws a small jab, singing, "20's on the drop/ Blue and yellow rocks/ Keke yelling stop/ Sisqó's album flopped."

Another song called "Shake Your Body" features Kelly addressing singers who have gotten rich by biting his style, and once again, he calls out Sisqó.

"It ain't really no beef," Kelly explained in January while visiting New York. "I just didn't appreciate how my man got on TV and said he was shutting it down when it came to R&B. I ain't gonna lie, it triggered me a little bit where I had to speak up on that."

Kelly also disclosed that he has yet another verse aimed at the Dru Hill frontman, where he calls him a "bum."

Although Jay-Z does not mention Nas' name on any of the six songs that have made their way to the streets several weeks before the release of Best of Both Worlds (see [article id="1451930"]"Jay-Z, R. Kelly Hype Joint LP With Hash Browns, Johnnie Cochran And A Pimp"[/article]), he does reference Nas' dis record "Ether."

"Don't you know I eat ether and breathe acid, weak bastards?" Jay rhymes on the album's title cut, which is produced by Megahertz.

A spokesperson for Roc-A-Fella said there is no definitive word yet as to whether the leaked songs will make the final version of the album. The spokesperson could confirm that the LP's first two official singles, "Take You Home (Body)" and "Get This Money," will be released to radio on Tuesday.

For a full-length feature about the lyrical battle between Jay-Z and Nas, check out [article id="1452212"]"Nas Vs. Jay-Z: Grade-A Beef." [/article]