Rocky IV proved just how deadly Dolph Lundgren's Ivan Drago was early in the movie by having him kill Carl Weathers' Apollo Creed. The threat of death hung over the showdown between Sylvester Stallone's Rocky Balboa and Drago throughout the movie. However, as it turns out, Lundgren almost actually killed Stallone when they were filming their fight in the climax.

“He hit me so hard he almost stopped my heart,” Stallone told a crowd at Cannes, according to Vulture. “I told him, ‘Why don’t we just do it? Just try to knock me out. Really cut loose as hard as you can.’ That was a really stupid thing to say. Next thing I know, I’m on a low-altitude plane to the emergency room, and I’m in intensive care for four days. And there are all these nuns around.”

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Stallone also recalled his initial reaction to meeting Lundgren. “And then Dolph Lundgren walked in, and I hated him immediately... I had to find a superhuman being as an opponent, someone who would be overwhelming.”

The actor explained why he thinks he had such a negative reaction to Lundgren, saying, “Oh, that’s right, he’s perfect … This is what I would imagine they would create as an athlete — someone who is literally perfect. Indestructible. Shoulders, calves, forearms, giant butt, neck, back, everything.”

2018's Creed II saw Lundgren reprise his role as Drago and saw the Russian prizefighter's son, Viktor Drago, face off against Adonis Creed. Stallone has since indicated that movie might be his final turn as Rocky.

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Directed by Adrian Grunberg (Get the Gringo), from a script written by Sylvester Stallone and Matt Cirulnick (Absentia), Rambo: Last Blood stars Stallone, Paz Vega, Sergio Peris-Mencheta and Yvette Monreal. It is scheduled to be released on September 20 in theaters everywhere.