Usher's producer has apologised to the R+B superstar for leaking music from his upcoming album online. Polow Da Don admits he recently placed unfinished tracks, including Love In This Club and Timbaland and Ludacris collaborations Moving Mountains and Dat Gurl Right There, on the internet. The studio wizard claims he leaked the tracks to build momentum for the Usher album, which doesn't yet have a release date. Da Don explains to MTV, "I actually leaked it, I'm the culprit. It's no secret. "I told him (Usher) when I saw him that I had to put my relationship on the line: `If it fails, I know you probably gonna be mad at me. I know you probably won't f**k with me anymore.' "When I spoke to Usher, he was like, `Maaaan, why'd you do it?'. He knew I leaked the record, he didn't have to ask. I was like, `What?' He said, 'You know you leaked the record.' "But he was getting good calls on it too. He wasn't mad, but he was like, `Why'd you do that?' Because everything has to be set up on their end. A video should be in place with an artist like that as soon as it drops. "Those are the things you risk, but it's working out beautifully... Girls love it."