#4 John Cena vs. Lars Sullivan

Over the past 3 months, we have heard countless times about a Lars Sullivan/John Cena feud heading into the Show of Shows, WrestleMania 35. However, when The Freak had an anxiety attack, it caused the program to be postponed indefinitely. The Leader of the Cenation was never going to appear at Royal Rumble so an angle where Sullivan would have attacked him prior to the event would have been an effective way to initiate the feud.
Fast forward to the post-WrestleMania Raw, Lars Sullivan finally made his main roster debut by attacking Kurt Angle. The Freak then continued making appearances and laying out Superstars. It doesn't take a genius to figure out where this angle might lead to eventually.
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The most logical way to proceed would be to have John Cena standing up to Lars Sullivan. The match can either take place at SummerSlam or later, depending on Cena's schedule. The match (if it happens) will definitely cement Lars as a top superstar just like Lesnar, when he defeated The Rock at SummerSlam 2002.