The poster for this year's SummerSlam is online and it kind of gives away plans for what they have lined up as the Smackdown main event for the show. We already know who will be in the Universal Championship match and that is shown on the poster. The same goes for the Raw and Smackdown Women's Championships.
However, John Cena, Jinder Mahal, and Shinsuke Nakamura are featured on the poster. So, that could mean that the plan is for Mahal to defend against Cena and Nakamura in a Triple Threat Match or, the less likely scenario, Cena will be added to the Universal Championship match with Roman Reigns, Brock Lesnar, Braun Strowman and Samoa Joe.
So far, here is what they've announced for SummerSlam and scroll down to check out the poster:
Brock Lesnar (Champion) vs. Roman Reigns vs. Samoa Joe vs. Braun Strowman
Jinder Mahal (Champion) vs. the winner of next week's John Cena vs. Shinsuke Nakamura match
Raw Women's Championship
Alexa Bliss (Champion) vs. Bayley
Smackdown Women's Championship
Naomi (Champion) vs. Natalya