#1. Extreme Rules 2015: The Architect's first PPV defense

While WWE has repeated its WrestleMania main events numerous times to mixed (and, clearly, many times identical) results at the next pay-per-view event, our most recent entry onto this list bumped a mid-card match from WrestleMania 31 into the main event of Extreme Rules in the WWE Network's very next special.
Seth Rollins and Randy Orton squeezed a ton of effort and WrestleMania spectacle, in addition to, empirically, the single greatest RKO in history, into their Santa Clara encounter, and The Architect's Money in the Bank cash-in in the show's main event put a target on his back bigger than the belt on his waist.
First in line to take a shot was Randy Orton, who felt he was owed the first championship opportunity by virtue of being the last man to defeat the new champion (and on the same night he became champion, no less); each man won a match on RAW to choose the match's two stipulations, with Orton beating Tyson Kidd and Cesaro while Rollins beat a fellow Authority member with whom he had a feud slowly burning, Kane.
Orton picked a cage match with his stipulation and, in a move that made kayfabe sense but made no sense in the context of presenting entertaining fake fighting, Rollins opted to ban the RKO from the match; naturally, this meant that the RKO had to make an appearance in the match, the twist being that Rollins used the move to incapacitate Orton and allow himself to exit the cage and retain his new title.
Which Worked Better?
The WrestleMania 31 match was an instant classic for a number of reasons, the two biggest of which being Rollins's willingness to go all-out in his WrestleMania solo debut and the spectacular finish. The Architect's high-flying offense looked magnificent in a stadium setting, and it's impossible to heap too much praise on the acrobatic way the pair set up the winning RKO.
Extreme Rules' stipulations restricted all of that, with the cage walls taking away Rollins's ability to fly as easily and the removal of the RKO eliminating many fans' only reason to stick with a Randy Orton match; they worked well with what they were given, but couldn't match what they put on weeks prior at the Levi's Stadium.
Becky Lynch has been challenged HERE.