Ironically the O'Jays' biggest selling single was the one that neither the vocal trio nor the songwriting/production duo of Gamble and Huff thought would hit number one. Even frequent engineer Joe Tarsia had grounds to dislike the record; he thought it sounded technically dull, not enough highs. Some thought it sounded too old-fashioned with all of its "shoop-shoops", which recalled '50s doo wop. The only believer the track had before its release was MFSB guitarist Bobby Eli, who felt something "special" was being created during the sessions which would become the So Full of Love album. Of course, when the track began its 20-something week chart run, "everybody" knew it was a hit from the start. The warm, smooth "Usta Be My Girl" sold more than a million copies, holding down the number one R&B spot for five weeks and peaking at number four pop in spring 1978. It was included on their platinum So Full of Love LP, which held the number one R&B spot for three weeks while going to number six pop, spawning the number 21 R&B ballad "Brandy" and the popular radio-aired album tracks "Cry Together" and "Help (Somebody Please)." The Four Tops' 1981 number one R&B/number 11 pop single "When She Was My Girl" is both similar in title and tone.