The “Rocky” movies may be scripted, but the blows landed by Sylvester Stallone and Dolph Lungren were all too real at times.

Stallone issued the documentary “The Making of ROCKY VS. DRAGO by Sylvester Stallone” ahead of the premiere of his “Rocky IV: Rocky vs. Drago” director’s cut. The behind-the-scenes featurette reveals just how serious things got in the boxing ring.

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Stallone revealed a fight scene with Lundgren almost resulted in his demise after a punch from the actor resulted in Stallone requiring intensive care.

“The first thing we shot [was] my entrance, [Lundgren’s] entrance, and the introductions and then I got really injured during the fight and I had to be flown into intensive care to California from Canada,” Stallone said, per Indie Wire. “[Lundgren] pulverized me. And I didn’t feel it in the moment but later that night my heart started to swell.

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“My blood pressure went up to 260 and I was going to be talking to angels. Next thing I know I’m on this emergency, low-altitude flight. I’m in intensive care surrounded by nuns and then after that, I had to go back and finish the fight.”

“Rocky IV” was released in theatres on Nov. 27, 1985. It earned more than 10 times its budget at the box office. The director’s cut of “Rocky IV” will have a one-night theatrical release on Nov. 11 before its digital wide release on Nov. 12.