John Cena and Nikki Bella
John Cena has slowly transitioned from WWE into a career with Hollywood in recent years. Pictured: John Cena (L) and Nikki Bella attend the premiere of Universal Pictures' 'Blockers' at Regency Village Theatre in Westwood, California, April 3, 2018. Christopher Polk/Getty Images

John Cena added fuel to the fire regarding a possible WWE retirement after a recent philosophical tweet following his Wrestlemania 34 loss to The Undertaker on Sunday night.

Cena challenged The Undertaker for well over a month to be his Wrestlemania opponent but received no response as he eventually attended the flagship event as a fan. After being told by a referee early on in the event that The Undertaker was presumably in the building, the 16-time WWE champion ran backstage and later came out to the ring anticipating the Deadman.

After an interruption from Elias, The Undertaker finally emerged and made quick work of Cena, defeating him in the quickest match of Wrestlemania in just under three minutes.

In the aftermath of the defeat, Cena posted a cryptic video of himself on Twitter playing The Animals’ "House Of The Rising Sun" on the piano in a somber black-and-white video.

Most recently, the West Newbury native posted a philosophical tweet on Thursday night.

"Life is funny sometimes," he wrote. "One minute it’s kissing and hugging on you, the next it’s kicking ya square in the nugget bag. Moments make the journey and the powerful play goes on."

Cena is known to troll a lot on social media but these recent tweets sparked speculation that a retirement may be close, especially after an interview this week where he claimed he is putting serious thought into what comes next after WWE.

"The fact that I've been able to do it at the pace that I have for 16 years, that's not your regular statistic," Cena told Peter Travers on "Popcorn with Peter Travers." "That falls into like the Tom Brady category. I'm not supposed to be where I am anyway. So I don't know when it's all going to end."

Cena was the face of the WWE for more than a decade since becoming WWE champion back in 2005 but in recent years, has slowly transitioned into Hollywood, which coincidentally is what he used to rip into Dwayne Johnson — The Rock — for during their rivalry from 2011 to 2012.

The 40-year-old is not full-time on the roster anymore and has notably not featured in the main event of Wrestlemania for five years now, after doing it five times in the preceding seven years before.

Instead, he has been featuring in a lot more movies, the most recent of which is "Blockers" which released Friday last week, while he is etching his name into the mainstream even more, having hosted the likes of "Saturday Night Live", the 2016 ESPY Awards and most recently last month at Nickelodeon's Kids' Choice Awards.

Cena may be closing in on retirement from sports entertainment but for now, he still has an upcoming match scheduled as he will be facing Triple H at the Greatest Royal Rumble event which takes place on April 27 in Jeddah, Saudi Arabia. It will be broadcast live on the WWE Network.