Josh Jackson, out of Kansas, reportedly cancelled his workout with the Celtics on Monday. Jackson is a possible top-three prospect and a player like him choosing to not workout with Boston could mean a couple of different scenarios

The first scenario is that he doesn't believe the Celtics are going to take him and doesn't want to risk a freak injury of some kind. That would be a weird decision on Jackson's part, but it's certainly possible. The assumption right now is the Celtics will take Markelle Fultz out of Washington.

However, there's another possibility for why Jackson chose to cancel his workout. Lots of players stop working out for teams once they get a promise from someone that they will be drafted by them. Rumors went around on Monday that Jackson possibly had gotten from the Lakers, but possibly from the 76ers as well. 

The Lakers are still in the process of working out players right now. Lonzo Ball worked out for them, but there were concerns about his conditioning. There have also been reports that De'Aaron Fox will get a workout with them as well. It would be weird for Los Angeles to make a promise to Jackson when they still have workouts planned, but it also wouldn't be out of the ordinary. Either way it looks like Jackson knows he's going somewhere in the top three at this point.