On last night's WWE Raw, something happened that's fairly unusual in the world of wrestling: one guy hit another guy.

After a WrestleMania date with The Rock, John Cena has been thrown into a feud with the newly signed Brock Lesnar. They opened the show last night with a staredown that quickly escalated into a fight, but this fight was not like other fights. Watch Lesnar's first punch after spearing Cena: a right hand directly in his grill. When the two were pulled apart, Cena's mouth was bloody. By all indications, this was an accident.

Wrestling punches are usually loud and theatrical, the wrestler stomping the mat to create a concussion as he curls and pulls his fist at the last millisecond before contact. But this was more of an MMA punch, which makes sense: Lesnar re-debuted in WWE just last week after a four-year career in UFC. Watching the video, Lesnar realizes he made solid contact. Successive punches are even more phony than normal. He avoids the face altogether.

Missed spots do happen—one knock on Lesnar during his first WWE go-round was that they happened a little too often. But last night's mishap put the WWE in a strange spot. In recent years, as a move away from the Attitude Era legacy and toward more family-friendly programming (Linda McMahon's Senate bid being a prime mover), blood has become a rarity. The culture of blading is cyclical: it was a crucial part of regional federations, then made a huge comeback in the late '90s as the WWE co-opted the success of ECW and Japanese wrestling. But these days, it's mostly saved for pay-per-views.

It's almost laughable, that arbitrary taboo. Show as many piledrivers powerbombs as you want, each of which would logically end in paralysis. Smash metal folding chairs across a guy's head—no problem. But a little blood, the only visible sign that these choreographed assaults are actually doing damage, and all of a sudden that TV-PG rating is in jeopardy.

So under normal circumstances, an accidental bloodletting would mean the production truck avoiding replays. But here was the WWE, their biggest star flashing a red smile, with two hours left to go in the show and countless replays to be shown. This is their biggest storyline, one that's going to last at least a month, and there was no way to avoid revisiting a backstage-clearing brawl between Cena and Lesnar. They dutifully showed replays throughout the show (noticeably clashing in tone with the preteen-appealing antics of Raw guest stars The Three Stooges), and the whole thing turned into a happy accident for the company. A real payoff for a real punch means real drama going forward, and the WWE unwittingly had a true "holy shit" moment—semi-unscripted.