Who doesn’t want to see two massive heavyweights go at it in a steel cage? Everyone wants to see explosive displays of brute strength and power, resulting in highlight-reel knockouts.In that regard, nobody can do better than the heavyweights of mixed martial arts. View this post on Instagram Instagram PostTwo of the world’s biggest MMA promotions, the UFC and ONE Championship, have an abundant pool of heavyweight talent on their respective rosters. It’s such a shame that they haven’t found a way to cross-promote and pit their fighters against each other. However, that doesn’t mean fans can’t speculate.After all, no big-time match ever happened without it being a dream match at first. Given the unpredictable nature of the sport, not only during fights but also outside of it, we can't be certain that some of these fighters will end up staying put or exploring their options.Whether in the Octagon or in the Circle, heavyweights from both promotions are always looking to put on a show. As fans, we can only dream. Let’s take a look at a few interesting dream fights in the highest weight class of combat sports.Here are three UFC vs. ONE Championship heavyweight matchups fans want to see.#3. Derrick Lewis (UFC) vs. Kang Ji Won (ONE Championship)Kang Ji Won has never let a fight go beyond the first round, which is a testament to his power and desire to finish a fight on his own terms. He is quickly becoming a fighter to watch out for in the promotion’s heavyweight division because of his exciting brand of fighting.Kang debuted for in the largest MMA promotion in Asia in 2021, knocking out his first two opponents, highly-regarded wrestlers Mehdi Barghi and Amir Aliakbari. He was never supposed to beat them, but came out of nowhere to post spectacular knockout spectacles. View this post on Instagram Instagram PostWhat better way for the 26-year-old to show the world just how legit his stopping power is than going up against the UFC’s Derrick Lewis?Even at 10 years older than the South Korean behemoth, Lewis continues to be a force in the sport, with his last three wins coming by way of knockout. His latest victory in December 2021 against Chris Daukaus gave him the record for most knockouts in the UFC at 13. View this post on Instagram Instagram PostA clash between these two titans would most definitely be a slugfest. Both like to fight on their feet and with the power behind both fighters’ fists, it could end in the blink of an eye.