In the weeks leading up to the draft, we haven't been sure whether the Boston Celtics would keep or trade their No. 1 overall pick. What we were pretty sure of, however, is that if they did keep the pick, they would use it on Markelle Fultz.

Turns out, we know nothing.

According to ESPN's Chad Ford, the Celtics aren't necessarily sold on Fultz, and they're strongly considering taking Kansas forward Josh Jackson with the top overall selection.

Markelle Fultz has been atop my Big Board since version 2.0, and his only real challenger most of the year has been Lonzo Ball. But Josh Jackson, who was No. 1 on Big Board 1.0, has emerged as an intriguing option for the Celtics and team president Danny Ainge (even though he canceled a workout with Boston this week, according to ESPN's Jeff Goodman and Marc Spears). "I've picked Danny's brain for years," one GM said. "Jackson is an Ainge player all the way. Tough, athletic, long, versatile, elite motor. If he's keeping the pick, Jackson just to me, far and away, is the most Celtics-type player for them to draft. From all my conversations with them, I'm convinced they'll take Jackson No. 1."

The plot thickens.

Boston taking Jackson instead of Fultz would send shock waves down the draft board. The Lakers, for example, are reportedly choosing between Jackson and Lonzo Ball with the No. 2 pick. If Fultz is available, however, they'd almost have to take him. The ripples would continue to team after team.

The Celtics have an All-NBA point guard in Isaiah Thomas, so it would make sense for them to go with a versatile forward instead. But if Fultz is the type of talent many believe he is, commissioner Adam Silver could still end up reading his name as the top pick in the draft next Thursday.