John Cena returned to WWE this week, appearing on Monday Night Raw as his 20-year career was celebrated.

Cena debuted on WWE's main roster on the June 27 episode of SmackDown in 2002, and with Monday's Raw taking place 20 years to the day after his first appearance, WWE brought him in for the show.

Cena was featured all over the show in promo packages and backstage segments, with the 16-time World Champion also cutting an emotional promo at the top of the third hour.

With Cena now having been in WWE for 20 years, a rather interesting side-by-side comparison has emerged of his first render, and his most recent one.

As you can see below, Cena has barely aged since 2002, which is pretty impressive, considering he's now 45 and walked into WWE in his 20s.

Cena, to his credit, looks just as ripped as he did back during his first year in WWE, and he has an intense training schedule to thank for that.

Cena was a full-time wrestler for 15 years, becoming more of a part-timer in 2017 as he embarked on a career in Hollywood.

That's proved to be quite successful for the WWE megastar, who has featured in some pretty big films and TV series over the last couple of years.

WWE will always try and bring Cena back where they can, but due to his busy filming schedule, that's sometimes quite difficult.

Many fans thought that Cena would be wrestling Theory at SummerSlam, and while that was teased on Raw this week, it certainly wasn't confirmed.

In fact, during his emotional promo, Cena suggested that while he definitely isn't done with WWE, he isn't sure when his next match is going to take place.

Unless plans are locked in for him to wrestle next month, and he's just working the fans, it seems unlikely that WWE would have Cena say that if he's going to be back next month.

Regardless, WWE will likely be looking to bring Cena back at some stage in the future, with WrestleMania 39 in Los Angeles in April 2023 surely a show that WWE will be looking at having all of its top stars involved in.

As of right now, there's no word on what WWE has planned for the 45-year-old when he is back, so make sure you stay tuned to GiveMeSport for any potential updates on that front.