In regards to Roman Reigns’ announcement this coming Monday on Raw, some have said that it would be to set up a match against Brock Lesnar at Summerslam, however, at the moment that doesn’t make sense because we are having a Lesnar/Joe match which will take place at Great Balls of Fire. That means we could see a rematch or any other opponent to step up as was said before.
Another scenario is that Reigns could announce that he will challenge the winner of Lesnar vs. Joe, after which there would be two possible options leading into SummerSlam.
The first option is that during or after Roman Reigns’ announcement, Braun Strowman will return and they run an angle which would get Reigns away from Lesnar and into a match against Strowman. Another scenario is that a SummerSlam match between Lesnar/Strowman will be pushed back.
The second scenario is that Reigns does indeed get Brock Lesnar at SummerSlam which would be a major change in direction as WWE wanted to save that match for WrestleMania. If that is the route storylines go, the company could still always come back with Lesnar vs. Reigns again next year in a rematch.
Source: Wrestling Observer Newsletter