Usher Cursed Out By L.A. Reid for Refusing to Record 'Yeah!' Says Rico Love

Usher's biggest hit single, "Yeah!" almost didn't happen, if not for his label boss L.A. Reid threatening him like a mob boss ... at least, that's how producer Rico Love remembers it.

The decorated singer/songwriter was a recent guest on Home Grown Radio where he looked back at his first big break -- writing the "Throwback" song on Usher's chart-topping "Confessions" album, which celebrates its 20th anniversary this year.

Rico says he was on hand when Usher first heard the demo to "Yeah!," written by Sean Garrett, which initially failed to impress the R&B megastar ... who flat-out refused to record the track.

Rico admits he also thought the song was corny -- he says the opening lyrics, "Up in the club with my homies/Tryin' to get a little V.I./Keep it down on the low-key" ... made him fall on the floor laughing.

On the other hand, Reid -- who was the President of Arista Records at the time -- heard a hit and demanded Usher push the song out ahead of the original first single, "Burn."

When Usher pushed back further, Rico says Reid didn't give him much of an option and told him to "do the f***** song" and hung up on him immediately after!!!

The tough love paid off in plaques ... "Yeah!" topped the charts for 12 weeks straight, and "Confessions" went on to be certified Diamond. Rico calls it great A&R'ing.