Lil Wayne's Young Money Sports -- Signs 1st NFL Prospect ... FSU Star Reggie Northrup

Lil Wayne isn't just coming after Birdman in the rap world ... he's gunning for him in the sports world too ... signing the first NFL prospect to his Young Money Sports agency, FSU LB Reggie Northrup.

Sources close to the situation tell us Wayne specifically targeted Northrup ... because Weezy was blown away by Reggie's work ethic and drive.

Those same sources also wanted to make one thing clear ... this is a YOUNG MONEY athlete ... there's no business relationship at all with Birdman's Cash Money Sports ... home to Bucs WR Mike Evans.

The whole Young Money business team is down in Tallahassee right now for Reggie's pro day ... and you gotta wonder if Birdman's gonna be able to hang on to his guys now that Wayne is making his own play.