#2 John Cena's planned match with The Undertaker at WrestleMania 32 was canceled
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At WrestleMania 32, John Cena didn't compete, and it was the first time since 2003 that he hadn't wrestled a match at The Show of Shows. Cena still showed up though, to help The Rock fend off The Wyatt Family.
Later that year, Bryan Alvarez of Wrestling Observer discussed WWE's plans for a Brock Lesnar vs. Shane McMahon match that never happened and revealed that WWE had planned to have John Cena wrestle The Undertaker at WrestleMania 32.
“I cannot bring myself to believe that they’re going to do [Shane McMahon vs. Brock Lesnar]. I just don’t understand why you would waste a Brock Lesnar match on Shane McMahon. The Shane vs. Undertaker match was a fallback plan after John Cena got hurt and they had nobody else for The Undertaker.”
At WrestleMania 32, John Cena made his surprise return and helped The Rock take down The Wyatt Family. The Undertaker defeated Shane McMahon inside Hell In A Cell.
Two years later, John Cena finally got to face The Undertaker at WrestleMania, but he was squashed in a match that didn't even last five minutes.