If UFC heavyweight champion Stipe Miocic was watching UFC 218 on Sunday, you could forgive him for breaking into a cold sweat as Francis Ngannou authored one of biggest knockouts in UFC history.
In what was billed as a title eliminator, Ngannou (now 11-1, 6-0 UFC) was meant to face his toughest test in the form of former title challenger Alistair Overeem (43-16, 8-5 UFC).
It was billed as experience versus power, a veteran of the game versus a powerful striker who nevertheless had only been training in MMA for three years.
Forget the experience. When you have the type of power Ngannou possesses, it really doesn't matter how long you've been fighting for.
If he hits you clean, you're going out, and the always-confident Overeen found that out the hard way.
He tried to bully Ngannou in the clinch against the cage but try as he might, the 2017 version of Overeem couldn't shift the six foot five, 265 pound Cameroonian.
One minute and 40 seconds into the first round, both men stood and traded.
Exactly two seconds later Ngannou exploded with a perfectly timed left uppercut that instantly knocked Overeem out, snapping his head back violently, sending him to the canvas stiff as a board.
If you didn't see it, to put it into perspective is almost impossible, but for argument's sake, try this. It made Dan Henderson's brutal overhand right knockout of Michael Bisping - one of the most iconic UFC strikes of all time - look like a love-tap.
UFC president Dana White confirmed Ngannou would not get a title shot against the reigning champion, who last defended his belt by knockout against Overeem at the end of the first round.
If Miocic is nervous, well, you can't really blame him.
Ngannou's power is such that if he lands one clean punch, that's it, there's no coming back and Miocic is hittable.
He's got a decent chin, but I suspect even Mark Hunt's legendary chin, at it's peak, couldn't take a Ngannou uppercut.
Miocic's wrestling is a step above Overeem's but Ngannou's sheer size makes taking him down an incredibly difficult proposition.
You can never count out Miocic but all evidence indicates this matchup will simply be a case of not if, but when Ngannou lands that one massive punch.
It seems like a forgone conclusion that only a performance for the ages by Miocic will prevent Ngannou being crowned the UFC's first African champion.
In the main event, Max Holloway was dominant in his title defence against legendary featherweight Jose Aldo, blowing away the former champion with a series of elbows in the third round.
Holloway is now such a complete fighter that with his 12 fight win-streak, he's already cleared out the division.
He was initially billed to take on New Jersey's Frankie Edgar and that matchup makes the most sense, but a clash between the winner of Cub Swanson and Brian Ortega would be a good alternative matchup.
In one of the best fights in UFC history, Eddie Alvarez turned back the clock and became the first man to stop Justin Gaethje with a perfectly timed knee in the third round.
Alvarez was relentless in working the body while Gaethje invested in ridiculously hard leg kicks, but ultimately Alvarez stayed on his feet and took a fight that would have won both men some new fans.
Alvarez in particular is in an interesting spot, as every fighter above him is currently booked.
A rematch with Dustin Poirier makes since, given the controversial no-contest decision of their first fight, while a fight between Kevin Lee and Gaethje would be an explosive matchup.