If Rondo plays or appears on the team sheet for the Memphis Grizzlies this upcoming season, he would have been on 9 different NBA teams, this ties a *record for an All-NBA player (with Kevin Willis). Given Willis played until he was 44 years old, that is a significant marker of a career slide.
If someone had told me after the 2012 season, Rondo would play for another 8 teams in his career, I wouldn't have believed them. I can understand after his ACL tear in 2013 he was never the same player but given many other former All-NBA stars have suffered traumatic injuries, you have to believe Rondo's stubbornness has been a major factor.
* This is based on my own research.