R&B singer Jeremih entered the scene in 2009 powered by the hit single, “Birthday Sex” and plenty of help from producers who knew how to stay in top 40 radio rotation. But by the next year, when his sophomore effort, All About You was released, one of his collaborators says the situation was totally different.

“They was counting Jeremih out completely,” 50 Cent revealed to Hot 97’s Angie Martinez. “On that project, he was already gonna be dropped by Def Jam—the first week sales were really low on the record. When we first did the song, I didn’t care. I was just looking at him as an artist—I thought he was dope artist.’”

The Chicago-bred R&B crooner initially only moved 17,705 copies of his second album. But the 50 Cent collaboration, “Down On Me” soon went viral after a video surfaced of a teen named Keenan Cahill dancing to the song in his bedroom. Cahill, who suffers from Maroteaux Lamy Syndrome parlayed his lip synching into 18 million YouTube views and an appearance on “Chelsea Lately.”

“I told him it’s number one—you heard my verse,” 50 joked. “I said, ’50 and Jeremih number one, there’s nothing higher.” The single didn’t reach the number one spot, but it did debut as the number 25 song in the country before spending another 19 weeks on the charts and peaking at the number nine spot.

[April 5]

UPDATE: 50 Cent and Jeremih received a platinum plaque last night for their collaboration single “Down on Me.” Watch a video of the two accepting the plaque during this past weekend’s Powerhouse 2011 concert.