most likely they would take Fultz or Ball and then trade Bradley or Smart for a big man. Doesnt help DJ to break through.
The Celtics like him though, so at least he knows he has a contract for several years, and if he just keeps playing well he will find a spot, either with the Celtics or someone else will want him as part of a bigger deal.
I hope he stays with the Celtics. They are really building something and he could be a part of a winning franchise for the next 10 years if it all works out well.