Song in Doris Day Rock Hudson Movie called pillow talk who are the other singers>?

In the movie singing along with Doris Day and Rock Hudson in the movie pillow talk there is a very strong voiced african american singer that actually sings the song and then asks ms Day's Character to sing along. Who was the lady singer and was that her band singing with her or was it another band that was hired. Love the song just cant find enough info on it and did not see that the singer was acknowledged in the credits.