John Cena attempted to ruin Brock Lesnar with a savage rap promo on WWE SmackDown in 2003.

Both debuting on the main roster in 2002, Brock Lesnar and John Cena are two of WWE's biggest-ever stars.

The pair have held 26 WWE World Championships between them, and main evented WrestleMania several times each.

The pair worked together a fair few times in Lesnar's second run with WWE, which started in 2012, but many fans don't really remember that they were involved with each other during Brock's first.

In fact, footage has emerged online from SmackDown in 2003, with Cena cutting one of his signature 'Doctor of Thuganomics' rap promos on 'The Beast'.

Cena tried to ruin Lesnar with his rap, which to be fair, featured some pretty savage lines about the former WWE Champion.

You can see a full transcript of Cena's rap below.

"This is serious now. Kill the beat. Kill the beat. People think I'm crazy, that's what everybody's telling me, because me beating you is like you winning a spelling bee. That's okay, tonight I silence them all. You're a neanderthal, so I'll use words that are small. Big Brock Lesnar, here comes the pain. God built me strong, forget to give me brains. You hop around all day like there are potatoes in your crack, that's a nice tattoo of your mother on your back. I'm untouchable, you can peep my ability, I'm like a basic math problem Brock, you just can't finish me."

Things didn't work out too well for Cena though, as just after finishing his rap, Lesnar immediately started to beat him down at the start of their match.

Brock ended up winning the bout too, so while John may have thought he did some damage with his rap, it was Lesnar who had the last laugh.

Fans online have commented on the clip after it resurfaced over the weekend, with many even going as far as to say that his version of John Cena was the best that we got in WWE.

Brock and Cena still remain with WWE to this day, but work part-time schedules, unlike back in 2003.

Cena is now full-time in Hollywood, but he does appear when his busy schedule allows him to, with a rumoured match at WrestleMania 39 in April 2023 set to be on the cards.

As for Brock, fans worried that he was going to retire after SummerSlam in July, but 'The Beast' is being advertised for WWE shows in 2023, so it looks like he's hanging around.