The depth of this current roster is pretty impressive overall. Yes, there is a need for a big, but I suspect a couple of things will happen to address that need. 1) DAnny will look for someone that is bought out at the deadline. 2) Fab Melo will be recalled in March and will play some.
That's not what the fans here want to hear, but barring a season ending injury to KG or maybe Pierce, that's likely what we will see happen, imo. And the better they play, the more likely this scenario is to play out.