Head Coaching Record: 28-72
Rings as an Asst: 9
Cleamons has been a longtime NBA assistant, mostly under Jackson. He won four rings with Jackson’s Bulls and five with Jackson’s Lakers. In between, he was head coach of the Dallas Mavericks for a season-and-a-half. He also served as the de facto coach of the Lakers on a number of occasions when Jackson was sick or tossed.
It’s likely Cleamons holds the record for most NBA head coaching positions considered, but not ultimately hired for. Cleamons’ most recent job came in 2011-12 as the head coach of Zhejiang Guangsha in the Chinese Basketball League. If it’s a defensive-minded, essentially career-assistant to Phil you want, I suggest looking no further than Cleamons.
The serious drawbacks to Cleamons? For one, he wasn't that great with the Mavericks (although, to be fair, they were very much in flux during his time in Dallas). For two, the offensive and defensive style he runs is quite complicated.