According to a Medium article about D.I.T.C.,

The first member of D.I.T.C. to officially release music was Diamond D, who teamed with rapper Master Rob to form the group Ultimate Force. They released one 12-inch single in 1989 on Strong City Records called “I’m Not Playing”, propelled by an expertly-freaked sample from Stax Records’ blues guitar royalty Albert King. Produced by Jazzy Jay, it would be the only song released by the duo, despite a shelved 12-track album produced almost entirely by Diamond D. A 2007 unearthing of that LP revealed the earliest known recordings by Fat Joe on “Another Hit” and “Oh, Shit”, respectively. Due to the album being shelved, we wouldn’t hear Joe’s voice for the first time until years later.