9. AJ Styles (WWE Championship)
It's easy to consider Kairi Sane's time with her title too short. But, the same cannot be said for AJ Styles' second reign, as he amassed a whopping 371 days as champion, proving that lengthy babyface runs are perfectly possible in the company's modern era.
2017 was an odd time for the World Title as Jinder Mahal had risen from obscurity to grab the belt and hold onto it for a bafflingly long time. But WWE brought Styles in to end this bizarre decision, and the pop he received was thunderous.
AJ's time with the title wasn't to everyone's taste, as he went over a fair few competitors who fans were hoping to take the gold for themselves - like Nakamura or Samoa Joe. Still, Styles brought a true sense of wrestling class to the championship, as he always delivered in his matches - as he's want to do - and worked incredibly hard to keep SmackDown relevant.
The Phenomenal One began calling himself the "face that runs the place" during his initial heel run on SmackDown Live, but it was this reign that truly brought that moniker to life.