Isaiah Jackson could be a defensive anchor for the San Antonio Spurs
Jackson has fantastic defensive instincts and the ability to cover ground quickly, which made it seem almost as though he were in multiple places at once. He's able to slide over and swat shots from the weak side in emergency situations, in the paint off of post-ups, and on the perimeter when closing out on open three-point shooters.
While that versatile shot-blocking ability may sound nice on paper, it also contributed to Jackson's struggles with committing fouls, averaging three per game. He would greatly benefit from learning how to identify shot fakes, which would help him to become a better rim protector and cut down on fouls. Fortunately, the Spurs have a track record of helping big men improve in that regard, namely with Jakob Poeltl, Tiago Splitter, and Aron Baynes, and could certainly help Jackson improve as well.
In addition to blocking shots, his agility could also make him a threat defending guards one-on-one, particularly off of switches. Jackson effectively defended smaller players by either keeping them in front of him or by sliding his feet well enough to keep up with guards or wings when they drove to the rim.
While adequately guarding smaller defenders is often difficult for big men, he’s displayed the potential to do so at the next level. Were Jackson to get drafted into the right situation like the Spurs, they could help him learn to use his physical tools to his advantage and become the team's anchor on defense.