Dave Meltzer noted that he has heard that Roman Reigns was decided on facing Brock Lesnar shortly before or after WrestleMania XXX. Many reports surfaced with Triple H and Vince McMahon at odds if it should be The Rock or Roman Reigns getting the championship shot at WrestleMania 31.
As for Brock Lesnar, he was not supposed to originally face John Cena at SummerSlam and Night of Champions. The original booking called for Brock Lesnar to come back and beat Daniel Bryan, which would “bring him back to reality.”
They wanted to book Lesnar to break the hearts of the fans, but the injury to Bryan caused for plans to change. That is when they decided on John Cena vs. Brock Lesnar.