John Cena once rejected a pitch from WWE Chairman Vince McMahon to act as a tweener who would be cheered in some locations and booed in others, per a former WWE creative writer.
On the We Watch Wrestling Podcast (h/t Dominic DeAngelo of Wrestle Zone), former WWE writer Matt McCarthy described the idea McMahon had for Cena, which was similar to what WWE did with Bret Hart in 1997:
"Vince kept trying to figure out how do we do like a Bret Hart thing? Where he's a heel in some places, but he's a babyface in the rest of the places.
“Cena was like, 'If I'm going heel, I want to go full heel,' and it did get close enough to the point where, and I'm sure he still has this gear, like Cena had gear made for the heel turn, you know? No longer the jorts."
Hart's 1997 character was something that had never really been done before or since in wrestling, as it saw him act as a big-time heel in the United States and a beloved babyface everywhere else in the world, including his beloved Canada.
It is unclear how WWE would have done something similar with Cena, but the 16-time world champion was apparently committed to going all-in either way rather than playing it down the middle.
McCarthy further discussed the heel gear Cena had made and explained why the heel turn never happened:
"I don't know what the gear was, but he had specific gear made ready and waiting and then obviously we know it never happened, and there was a point in the discussions where it was like, 'Well, the people who are gonna cheer him are going to continue to cheer him, and the people who are gonna boo him, are just gonna keep booing him.' So the thinking was, that's the most heelish thing he can do is to stay that white meat, smiling, pure babyface."
Even though a turn never happened, Cena essentially was a tweener for the final few years of his full-time run in WWE with a fairly equal amount of the fanbase both cheering and booing him.
A Cena heel turn likely would have been the biggest turn since Hulk Hogan became Hollywood Hogan in WCW in 1996, but refraining from doing so arguably made Cena's career even more special.
Aside from a brief run early in his time with WWE, Cena has never been heel, which is something very few wrestlers can say.
There is still time for a heel turn, but the remainder of Cena's wrestling career will likely be as a part-timer given his acting commitments in Hollywood, which doesn't provide WWE with much incentive to make the switch.
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