WWE's top championship has been booked as on the line during the Royal Rumble match on two occasions. In 1992, the vacant WWF World Heavyweight Championship was contested in the 1992 Royal Rumble match, which was won by Ric Flair, while in 2016, Roman Reigns was scheduled to defend his WWE World Heavyweight Championship as a participant of that year's Royal Rumble match as entrant number one. This has thus far been the only time that a reigning champion had to defend his title in the match, which was ultimately won by Triple H, who eliminated Reigns before lastly eliminating Dean Ambrose to win—Reigns would earn a rematch against Triple H at WrestleMania 32 and won back the title. In 2020, although he did not defend his title in the match, WWE Champion Brock Lesnar entered the Royal Rumble match as entrant number one, feeling as if no one on any brand deserved to challenge him at either the Royal Rumble or WrestleMania. This was the first time in which a reigning world champion competed in the match in which the winner could challenge them—Lesnar's participation was used as a way to set up his WrestleMania challenger, which ended up being Drew McIntyre, who eliminated Lesnar, won the Rumble match, and then challenged Lesnar for his title at WrestleMania 36.