#1 John Cena and Batista

Both John Cena and Batista are multiple time WWE Champions--withe the former having performed for WWE's developmental territories since 2000, until he broke through as a major star on the main roster in 2002.
On the other hand, Batista worked for the WWE from 2000 to 2010--with his rise to prominence paralleling that of Cena's timeline in the company. Addressing his 2010 departure from the WWE, Batista made it no secret that he disagreed with the PG direction WWE seemed to be heading in after the revolutionary changed in the company back when it adopted PG norms in order to put forth a more child-friendly product from 2008 onward.
Cody Rhodes' uncle is a WWE Hall of Famer. More details HERE.
In addition, the professional wrestling world was rife with talk of backstage heat between Cena and The Animal through the 2000s--with Batista noting that Cena's WWE character is something he disagrees with, especially given how he hates the PG direction of the company. While Batista refrained from commenting further on the issue, during his brief return to WWE which lasted from 2013 to '14, talk of Batista's backstage heat with several WWE Superstars including John Cena once again gained steam.
Well, when one places a couple of intensely competitive individuals such as Dave Batista and John Cena in a tense, cut-throat world such as that of pro-wrestling--tension and disagreements are indeed inevitable.
Which other real-life rivalries between WWE Superstars and pro-wrestlers in general would you like to hear about? Your opinion matters, and this writer is here to shed light upon stories untold. Please provide us your feedback in the comments section below...