WWE superstar Big Show -- who's fought guys like Hulk Hogan, Floyd Mayweather and John Cena -- has a warning for newcomer Cain Velasquez -- there's NO ONE as scary as Brock Lesnar!!!
TMZ Sports spoke with the wrestling legend about the ex-UFC star's upcoming fight with Lesnar at 'SmackDown' on Friday ... and we had to ask if Cain has a snowball's chance in hell at winning his first match.
"I'mma be real honest with you, I’ve been wrestling for 25 years, I have never seen a monster like Brock Lesner and the warpath that’s he’s been on for the past few years," Show tells us at LAX.