John Cena returned to WWE after 15 months away from the ring on Sunday night, facing off with 'The Fiend' Bray Wyatt at WrestleMania 36. 

The 16-time world champion has been on hiatus since January 2019 and competed in a Firefly Fun House match, which many fans think stole the show.   

There was very little actual wrestling and it was more of a cinematic experience, with The Fiend delving deep inside his opponent's mind to gain a psychological edge.

It began with Cena revisiting various eras of his career - including his Ruthless Aggression debut - and we even saw him as a member of NWO in WCW Monday Nitro. 

Bizarre right? But a masterpiece, none the less.  

Interestingly, many fans quickly noticed Cena is in very different shape compared to the last time he competed in WWE, sporting a very lean look. 

Check out images from his match with Wyatt below: 

Now, compare that physique to the one Cena was sporting back in 2018: 

That's quite a body transformation - he's cut serious weight and it didn't take long for fans to comment. 

"Wow John Cena looks so small compared to his usual look...it's odd seeing him that size," one fan wrote on Twitter. 

Another added: "John Cena has lost a good bit of size. It was noticeable tonight. He’s obviously still in great shape, but he’s definitely not as swole."  

One fan even thinks the Leader of the Cenation is in the best shape of his career, tweeting: "John Cena in better shape than he was 14 years ago."

It's incredible to think he's 42 years old. WrestleMania's Firefly Funhouse was a great watch, but it would have been good to see Cena actually wrestle, considering he's been away for so long. 

Given the ending to the match, his next WWE appearance will be anyone's guess.