SummerSlam already has a 10 match card, but even though matches are still being announced and many others are having stipulations added, it's already been made obvious that there are certain matches that won't be part of the card.
The Intercontinental Championship won't be defended as part of the show as of writing, whilst, there isn't a single tag team Championship being defended on the show as Nikki Cross, Alexa Bliss, The OC and The New Day (aside from Kofi Kingston) have seemingly been given the night off.
Whilst these matches weren't actually expected to be part of the card, there were a number of rumored matches last month that the company could have easily added to the show, but many of them have since been nixed.
#5. Rey Mysterio vs Andrade
Rey Mysterio has had a rocky few years since he made his return to WWE but is still a former United States Champion. Whilst the masked star has been part of a feud with Andrade on SmackDown Live already, WWE decided to rehash the issues between the two men in recent weeks when Andrade eliminated Mysterio from the Gauntlet match on Raw a few weeks ago.
Following the elimination, Andrade ripped off Mysterio's mask and started the rumors that the two men would do battle once again in Toronto in a Hair vs Mask match.
Mysterio and Andrade faced off on Raw before The Master of the 619 was part of a match with Dolph Ziggler on SmackDown Live. It was then reported by The Wrestling Observer that the match that was originally set to take place at WrestleMania 35 was nixed for safety reasons. The match has since been nixed from SummerSlam as well for seemingly the same reasons since Mysterio isn't ready to lose his mask and Andrade is thought of highly backstage so the company are not willing to hand him the loss.