This is a tough one to make the list because the pairing of Cena and Brock Lesnar makes sense from a storyline perspective and has produced really good matches. Lesnar is arguably the biggest free agent signing WWE has made in the past decade. And he immediately matched up against Cena. He then faced Triple H for an unjustified three straight matches before beating Punk, Show and Taker. Now, Lesnar is back to Cena, battering the former champ at two straight PPVs before taking a break.The argument has been made that WWE World Heavyweight Champion Lesnar could elevate others with title shots rather than giving Cena a third straight match. Additionally, it doesnt look like Cena-Lesnar is moving the needle with PPV or WWE Network buys, so whats the purpose? The answer could be that Lesnar makes Cena look vulnerable. Sure, Cena will occasionally lose a match, but he rarely will look outmatched. Making Cena the underdog against a scary Lesnar is one way to try to transfer some heat to him.