John Cena is responsible for tearing into Roman Reigns during a feisty promo on an episode of Monday Night RAW a few years back.

The former is an all-time great in the history of WWE, having won the WWE Championship 13 times, the World Heavyweight Championship three times and the World Tag Team Championships four times.

Reigns, meanwhile, joined WWE in 2010 following a short career in American football and is one of, if not the, best wrestler there currently is. He is also the Universal Champion right now and delivering some of his best work to date on a weekly basis on SmackDown.

There have been several professionals who were touted to be the "next John Cena" at some point of their careers. However, Reigns was one who many thought had the potential to have the same kind of legacy or even bigger than the 44-year-old. 

However, when the two shared a ring back in 2017, Cena showed his peer there are levels to WWE and he wasn't quite there yet.

Cena, who has been a protagonist throughout most of his WWE career, is well known for living up to his popular catchphrase "Hustle, Loyalty, Respect". However, back in 2017, during a promo for Monday Night RAW, the 44-year-old absolutely tore into Reigns and it was when the Big Dog forgot his lines that it turned seriously savage.

At around halfway through the below video (07:30), Reigns seems to forget his lines and doesn't say anything for around 30 seconds before calling Cena a "phony", a "yes man" and a "part-timer," while accusing him of "burying young talent to stay at the top of the mountain."

The latter retaliated by calling him a fool. Cena ended his tirade by saying: “When it comes to this yard, you probably haven’t learned it yet. There’s only one rule; Step up or step aside. And over the years there’s been a few to step up, but nobody to ever keep up. And then I finally hear about this one guy. The guy.

"The Roman Reigns. The one that can keep up — and now I look at you, and I listen to you. You should be ashamed I’m a part-timer, because I can do this part-time better that you could ever do it full-time".

At the time, there were a few fans who were questioning whether Cena's lines were scripted or not. Given that neither have commented on the promo for almost four years, I guess it is safe to assume that it was written and unlike Reigns, the 44-year-old did not forget his lines.

Lately, there have been rumours of Cena featuring at SummerSlam in July and that he could face Reigns in front of a crowd of 60,000. It will be interesting to see if that really happens and if it does, it will be one heck of a fight to see.