The biggest heavyweight fight in over a decade had something for everyone, but in the end it was Anthony Joshua who finally turned things around for good in the 11th round.
Here is how the world of sport and its fans have reacted to the spectacular showdown on social media.
Tyson Fury, who beat Klitschko to become world heavyweight champion in 2015, said: "Wellldone @anthonyfjoshua good fight, you had life & death with @Klitschko & I played with the guy, let's dance ='."
Former heavyweight champion Lennox Lewis said: "Crackin' Fight!!! Congrats to both for giving the fans something to talk about! Big up to AJ on the big win!!! How much heart did @Klitschko show in this fight? Gotta respect it. Hold ur head high brother! #joshuaklitschko."
Ex-boxer Frank Bruno said: "The heavyweight division just got very exciting,the performance of both men 2night was incredible,whats next, looking 4ward 2 finding out."
Nicola Adams, two-time reigning Olympic boxing champion, said: "Well. done big man you showed some heart and determination @anthonyfjoshua congratulations #JoshuaKlitchsko."
Former Olympic heptathlon champion Dame Jessica Ennis-Hill said: "What an absolute legend! Unbelievable fight! So proud of @anthonyfjoshua. I'm exhausted just watching = incredible!"
Ex-England and Arsenal forward Ian Wright said: "Delighted for @anthonyfjoshua."
Singer Robbie Williams: "Incredible x @anthonyfjoshua. Respect mate x @Klitschko."
TV personality James Corden: "Unbelievable AJ, unbelievable @anthonyfjoshua x x x."
West Ham chairman David Gold: "What a fight. Well done Anthony Joshua. Respect to Wladimir Klitschko. dg."
Arnold Schwarzenegger, film star turned politician, said: "One of the most exciting fights I've ever seen. Congrats @anthonyfjoshua on the win & @Klitschko on amazing battle. Hope there's a rematch."
TV presenter Holly Willoughby: "This is so stressful I just had to go and unload the dishwasher!!!! #cantlook. Oh thank god!!!!! Huge congrats @anthonyfjoshua."
TV presenter Eamonn Holmes said: "Well that was a scrap and a Half ! A Privilege to be at one of the Great Title Fights. Congratulations Anthony Joshua Champion of The World."
Lewis Hamilton, the three-time Formula One champion, said: "Well done to both Anthony and Wladmir, but a huge congrats to @anthonyfjoshua for bringing it home! Great fight! #bigupyourself ====== =Y=Y=Y."
England rugby union forward James Haskell said: "Take a bow @anthonyfjoshua. What a warrior wladimir klitschko was on the night. But Joshua too..."
Footballer Joey Barton said: "Great fight that. Klitschko what an effort. Joshua answered lots of questions tonight. What a finish. =`=+=`=+."
England cricketer Steven Finn: "Going to add to the hoards of tweets. Amazing fight for Anthony Joshua. Love Klitschko. Humble to the core. How sport should be played. =`."
Michael Owen, the former England striker, said: "I'm so happy but wow, that was lucky. Massive learning curve for Joshua. Feel for Klitschko, great champ. The show rolls on."
Motor racing driver Paul Di Resta said: "After watching that fight I think I will stick to race cars. Awesome, but that looked hard work watching. #Joshua."