The Celtics could easily stretch someone and get under the cap enough to afford to waive a couple low money players and take on minimum contracts to replace them.
I'd rather take a chance on someone like Austin Daye who I think is a steal still out there or Luke Babbit than waste more time, roster spots, and money on Fab Melo.
Brooks has to be tradeable, I mean he has shown the ability to score, is on a rookie contract and has only one guaranteed season left. Someone would want him and probably give up something of value for him.