While the initial reports were that the John Cena injury was a work, Cena's injury last night on RAW was legitimate. The later show segments involving Cena went as planned but were shot live to incorporate the possible injury.
ORIGINAL: John Cena posted the following, via Twitter, regarding his "injury" from RAW last night.
"I am headed to Grand Rapids right now for early morn MRI on left knee WWE no matter what the result, I will be in the ring tomorrow!"
Cena is scheduled for tonight's SmackDown tapings.