The Rock and John Cena will go down in history as two of the most successful WWE superstars of all time.
In the ring, they both achieved it all. The leader of the Cenation is a 16-time world champion, while Rocky follows closely behind with 10 reigns.
Both are guaranteed Hall of Famers - and have also been successful outside of the wrestling world, each embarking on their own acting careers.
With all their similar success, you'd assume that the pair would get on pretty well together - but that, apparently, has not been the case.
Cena and The Rock battled it out twice in back-to-back main events of WrestleMania 28 and 29.
Normally, the beef between two wrestlers is just kayfabe, but in this case, Cena and Rock genuinely did not get along.
Finally, over five years later, The Most Electrifying Man in Sports Entertainment has revealed how his hatred with Cena started in the build-up to their huge 'Mania matchups.
"I had left, and John Cena had done a series of interviews," The Great One explained while appearing on "Watch What Happens Live", per ProWrestling.com.
"I just felt, and somebody had referenced me and said, ‘hey, is Rock ever coming back’, and he said, ‘I’m not quite too sure’, and I just didn’t like how he said it, and it stuck with me.
"So years later when I went back [to WWE], I talked to Vince McMahon and we thought, ‘well what if we took that and actually created this kind of thing,’ and I said ‘perfect’."
In essence, their epic beef started because the 16-time champ said some things that The Rock didn't agree with - and it grew into one of the best feuds of recent memory.
Now though, all these years later, it seems that the wrestler turned actor is over it. So much so, that Cena is going to star in one of Johnson's new movies.
SQUASHING THE BEEF
"I think we’ve squashed that [beef]. As a matter of fact John is gonna star in one of my movies that I’m producing," he revealed.
"I think he’s going great, he’s done great in his transition and he really wants to continue to work hard."