WWE's annual Royal Rumble pay-per-view is never complete without surprise entrants in the titular matches, and here's who showed up in 2019. While it wasn't the case in the early years, once it became entrenched as a WWE tradition, the Royal Rumble match became famous for its propensity to include participants fans wouldn't expect. It's almost a game for fans at this point, trying to guess what random retired legend, brand new signing, or NXT sensation will make an unadvertised appearance in the Rumble.

With last year's advent of the 30-woman Royal Rumble match, that's become even more of a fun activity, as a combined 60 entrants leads to lots of opportunities for the unexpected. While the 2019 Royal Rumble matches weren't quite as surprise-packed as some previous editions, there were still some inclusions sure to bring a smile to the face of wrestling fans. Before the list of proper surprise entrants begins, it's also worth mentioning that Hornswoggle the leprechaun made a hilarious cameo in the women's Rumble, chasing the cowardly Zelina Vega out from under the ring.

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Going into Sunday's Royal Rumble pay-per-view, WWE had officially announced 20 entrants for the men's Rumble match, and 23 for the women's. However, R-Truth didn't end up competing in the men's match, and Lana didn't end up competing in the women's. This left 11 possible surprise slots open for the men, and eight for the women. Surprise participants in the men's Rumble included: Jeff Jarrett, Kurt Angle, Johnny Gargano, Pete Dunne, Aleister Black, Dolph Ziggler, and Nia Jax. Surprise participants in the women's Rumble included: Xia Li, Kairi Sane, Maria Kanellis, Candice LeRae, Kacy Catanzaro, Io Shirai, Rhea Ripley, and Becky Lynch.

For those wondering, the other four possible surprise slots for the men were filled by regular roster members Shinsuke Nakamura, No Way Jose, Curt Hawkins, and Shelton Benjamin, so you can't really call them big shocks. His Rumble appearance represents recent Hall of Fame inductee Jarrett's first match for WWE since 1999. Fellow Hall of Famer Angle's entry marks his first appearance in the standard 30-man Rumble since 2005.

Gargano just won the NXT North American championship at Takeover on Saturday, while Dunne is the current NXT U.K. champion. Black just battled Tommaso Ciampa for the NXT title at Takeover, while Ziggler was returning from about a month's hiatus. Jax's entry was the biggest news, becoming only the fourth woman to enter the men's Rumble match after beating down R-Truth and taking his spot. It's rare to see men fight women in today's PG-rated WWE, so it was a bit surreal to see Jax get taken out by the likes of Randy Orton and Rey Mysterio.

Li and Shirai are rising players in NXT, after having competed in the Mae Young Classic tournament. Sane won that tournament before, and is a former NXT women's champion. She was also a surprise entrant in 2018. Catanzaro is a former American Ninja Warrior contestant, and is now part of NXT. Ripley was the first NXT U.K. women's champion, while LeRae is another rising NXT talent, and also the wife of Gargano. Kanellis spends most of her time managing her husband Mike, and rarely competes for WWE. Lynch - the eventual winner - took the spot of an injured Lana, after losing to SmackDown Women's Champion Asuka in the opening match.

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