Julianna Pena pulled off one of the biggest upsets in MMA history by ending Amanda Nunes' bantamweight title reign at UFC 269. "The Venezuelan Vixen" shrugged off the tag of being a massive underdog to submit Nunes with a rear-naked choke in round two of their fight.Pena's iconic victory sent the internet into meltdown, and while the MMA world was predictably stunned, several professional wrestlers also reacted to the fight on social media.Former MMA fighter Shayna Baszler was one of the first WWE stars to react to Pena's unbelievable win, and many other wrestles followed suit.Natalya, Ricochet, Lince Dorado, Marko Stunt, Joey Janela, and other wrestling personalities put out tweets following the massive upset, and we've compiled the best of the lot below:Shayna Baszler@QoSBaszlerShe didn’t just beat Nunes. She didn’t even have hooks in. She broke Nunes. We live in bizzaro world, now. #UFC26910:36 AM · Dec 12, 20215865711She didn’t just beat Nunes. She didn’t even have hooks in. She broke Nunes. We live in bizzaro world, now. #UFC269Nattie@NatbyNatureYes! 😱 twitter.com/qosbaszler/sta…Shayna Baszler@QoSBaszlerShe didn’t just beat Nunes. She didn’t even have hooks in. She broke Nunes. We live in bizzaro world, now. #UFC26910:37 AM · Dec 12, 202116714She didn’t just beat Nunes. She didn’t even have hooks in. She broke Nunes. We live in bizzaro world, now. #UFC269Yes! 😱 twitter.com/qosbaszler/sta…Nattie@NatbyNaturePENA IS A BADASS!!!!!! #UFC269 #AndNew10:31 AM · Dec 12, 202122715PENA IS A BADASS!!!!!! #UFC269 #AndNewRicochet@KingRicochetYOOOOOOOOOOOOOOOOOOOOOOOOOOO!!!!!!!!! 🤯🤯🤯🤯🤯🤯🤯🤯🤯 What! A! Fight!!! #UFC269 #ANDNEW10:34 AM · Dec 12, 202140141YOOOOOOOOOOOOOOOOOOOOOOOOOOO!!!!!!!!! 🤯🤯🤯🤯🤯🤯🤯🤯🤯 What! A! Fight!!! #UFC269 #ANDNEWThe Big Guy Ryback@RybackCongratulations to Julianna Peña, that was incredible! 🔥 Nunes such an amazing run! 👏 👏10:34 AM · Dec 12, 2021425Congratulations to Julianna Peña, that was incredible! 🔥 Nunes such an amazing run! 👏 👏Lince Dorado@LuchadorLDPeña! #UFC26910:34 AM · Dec 12, 2021603Peña! #UFC269Glenn Gilbertti@TheRealDiscoWow #UFC26911:02 AM · Dec 12, 20217Wow #UFC269“The Bad Boy” Joey Janela@JANELABABYJust threw 100 on Pena, god bless my soul.. #UFC26910:20 AM · Dec 12, 2021838Just threw 100 on Pena, god bless my soul.. #UFC269“The Bad Boy” Joey Janela@JANELABABY#UFC26910:33 AM · Dec 12, 202116216#UFC269 https://t.co/Xf7MCa5hJg“The Bad Boy” Joey Janela@JANELABABYOmg omg omg #UFC26910:30 AM · Dec 12, 20211043Omg omg omg #UFC269Nash Carter@NashCarterWWEOH MY GOD!!!!! PEÑA DID THAT!!!!! #UFC26910:31 AM · Dec 12, 2021461OH MY GOD!!!!! PEÑA DID THAT!!!!! #UFC269AJ Ferrari@mrfasttwitchWow what a fight🥊 Congrats to @VenezuelanVixen - it all started with her jab🤛🏼. But @Amanda_Leoa is still the 🐐 in my eyes. She will come back stronger from this. Someone may have just woke a lion 🦁 #rematch #ufc269 #amandanunes #goat10:42 AM · Dec 12, 2021172Wow what a fight🥊 Congrats to @VenezuelanVixen - it all started with her jab🤛🏼. But @Amanda_Leoa is still the 🐐 in my eyes. She will come back stronger from this. Someone may have just woke a lion 🦁 #rematch #ufc269 #amandanunes #goatCharly Arnolt@CharlyOnTVJULIANNA PENA 👊🏽👊🏽 wowwwww!!! #UFC26910:31 AM · Dec 12, 202119111JULIANNA PENA 👊🏽👊🏽 wowwwww!!! #UFC269Alex McCarthy@AlexM_talkSPORTJulianna Pena beats Amanda Nunes!!!Absolutely wild fight. #UFC26910:32 AM · Dec 12, 2021552Julianna Pena beats Amanda Nunes!!!Absolutely wild fight. #UFC269Jon Alba@JonAlbaPena!10:32 AM · Dec 12, 202181Pena!Dave Meltzer@davemeltzerWONThis was one of the biggest upsets in MMA history.10:31 AM · Dec 12, 2021741107This was one of the biggest upsets in MMA history.Julianna Pena ends Amanda Nunes' historic run as UFC Champion - As it happenedAmanda Nunes walked into UFC 269 as the undisputed favorite, and most MMA fans and pundits predicted another routine victory for the Lioness. The incredibly determined Julianna Pena, however, had different ideas.Nunes started the co-main event at UFC 269 in a predictably aggressive style as she knocked Pena down to the mat with a calf kick. The Brazilian legend looked like her usual self in the opening round as she managed to force Pena to employ a defensive style.The Venezuelan fighter weathered the storm and came out strong in the second round by using her jabs to significant effect. Nunes is known to dominate her opponents on the feet, but Pena was willing to stand in the pocket and engage with the champ.A furious exchange of strikes followed, with both women landing some hard strikes. Pena showed her toughness by absorbing the incoming punches and responding with stiffer shots.Julianna's onslaught eventually paid her dividends as Nunes left herself vulnerable to a clinch takedown. Pena took Nunes to the ground and quickly locked in the RNC to force the tap out of her opponent.Pena's win effectively ended Nunes' seven-year undefeated streak, and she did so in emphatic fashion.What did you think of this weekend's huge UFC upset? Share your thoughts in the comments section below.