I made it to the rack, even though they tried to box me out
He made it to the rack (success/Rocnation) even though some people tried to keep him away.
This is also a metaphor for basketball. Boxing out is a defensive technique in basketball used to keep players from getting to the ball. Good metaphor!
Rack could also refer to him having made it to the shelves, as he has finally released his debut album. Triple entendre?
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