The closer I look at it, the more I think there's a non-0% chance Obi falls to the Spurs. I wouldn't classify it as a good chance but it's difficult to find a landing spot for him in the top ten.
Minnesota: Would they really put a non-defensive big next to KAT? That'd be dumb.
Golden State: They have Draymond and Obi wouldn't be too helpful as a small ball center.
Charlotte: MJ likes going with the most well-known college player but, then again, they just drafted PJ Washington in the lottery last year and he was a started all year. You can't start Washington and Obi together.
Cleveland: Their guards are so bad at defense that picking Obi would defensive suicide. Plus, with Love and Drummond, things would get awkward pretty quickly.
Chicago: They already have an offensive, no-defense big in Markkanen.
Atlanta: Obi next to John Collins would be the worst defensive big pairing in the league.
Detroit: They have Blake Griffin and, more importantly, they desperately need guards.
Knicks: They have a ton of power forward who are light on defense. Would they draft another one? It's possible but they too need guards.
Washington: Rui looks like he's their power forward of the future. Add in Bertans, who they are expected to re-sign, and I don't see the fit here.
Phoenix: They have Saric and Cam Johnson. Ayton doesn't have good defensive instincts so pairing him with Obi would be dangerous.
The best fits for Obi are behind the Spurs: Portland, Boston, New Orleans, Orlando, etc.
The most likely team to pick Obi before the Spurs I guess would be the Cavs. He's an in-state product and it's not like they know what they're doing anyways. The Knicks are another team that would just draft him for the name.