10 WWE Superstars John Cena Only Wrestled Once
1. Jeff Hardy

Speaking of TNA performers who may or may not return to WWE, is there anyone out there who doesn't foresee one last Jeff Hardy run in the biggest sports entertainment company in the world? From the moment Jeff left in 2009 there seems to have been an inevitability about his return, and now that his house seems, the chances of a comeback will only grow.
John Cena and Jeff Hardy only had one singles match against each other on WWE TV, but as one would expect it was a damn fine match. It came in the summer of 2008, when Cena was getting closer and closer to working out his big match formula. and whilst Jeff was simply on fire as a rising top tier babyface. The styles meshed perfectly, Cena working a grounded slow style whilst Jeff did everything he could to up the tempo.
The match was to decide the number one contender to Triple H's WWE Championship, and whilst Cena winning felt somewhat underwhelming, the showcase these two men put on was fabulous. Hardy would be gone from the company just over a year later, and whilst that move deprived us of more Cena/Hardy matches, it was clearly for the best in the long run.
This is a match we may yet see again, but the one time we did get to see it it more than delivered. The 'Once in a Lifetime' status accentuates that. How would Cena's match with The Rock at 'Mania XXVIII be remembered if it was left as a Once In A Lifetime deal? We'll never know.