In the NBA, deals are almost always made at the last minute. Groundwork is laid in advance, terms negotiated, but it usually takes a deadline — say, the NBA Draft — to get both teams to sign the deal.
Which is why, despite the fact the Celtics and Sixers are serious and deep into talks about swapping the No. 1 and No. 3 picks (with Boston getting some future first rounders under Philly’s control), there has been a “slow your roll” sense about the momentum around this. If it happens, it likely does not happen until Draft night, after the picks are made. It’s something Keith Pompey of the Philadelphia Inquirer Tweeted about.
Another part of that is Philadelphia has yet to speak to (or look over the medical records) of likely No. 1 pick Markelle Fultz.
Most likely this goes down as expected: The Celtics draft Fultz, the Lakers take Lonzo Ball at No. 2, the Sixers pick Josh Jackson (who the Celtics like), then the trade is finalized, and Adam Silver lets us know from the stage about 15 minutes after Adrian Wojnarowski Tweeted it out.
But with time between now and the draft, things can change. Nothing is set until everyone signs on the line that is dotted.