Ex-Tennessee defensive end Derek Barnett tells TMZ Sports he was nervous when his name was called to be drafted by the Eagles Thursday night ... because he was afraid of being booed!!!

Fortunately, that didn't happen -- most Eagles fans realized quickly this dude is a beast!!!

Barnett says he's stoked to begin his NFL career in Philly -- especially since he's a huge Meek Mill fan ... and Philly is Meek's turf.

One more thing ... yeah, his brother totally looks like Pitbull.