Dolph Lundgren claims that he doesn't remember hospitalizing Sylvester Stallone when the pair were filming Rocky IV. The 1985 film pitted Stallone's revered Heavyweight Champion of the World against Soviet captain Ivan Drago (Lundgren), disconcertingly known as "The Siberian Express," after Drago killed Rocky's close friend Apollo Creed (Carl Weathers) in the boxing ring. A director's cut, entitled Rocky IV: Rocky Vs. Drago, was recently released to commemorate the film's 35th anniversary, featuring various changes to the original film, such as omitting the iconic boxing glove opening.

Despite a lackluster critical reception, Rocky IV proved to be Lundgren's breakthrough performance, earning him further parts in films such as Masters of the Universe, The Punisher, and Universal Soldier. The Swedish star also maintains an active collaborative relationship with Stallone, appearing in the director's action-loaded Expendables franchise as well as reprising his role as "The Siberian Express" in Creed II, in which the sons of both Drago and Creed renew their fathers' fateful face-off over 30 years later. But whilst the pair's initial partnership on Rocky IV proved to be a huge commercial success, its production was marred by more than a few mishaps, most notably that Stallone was hospitalized after Lundgren hit him so hard that his heart hit against his rib-cage, leaving the star in intensive care for nine days.

Related: Rocky V Needs A Stallone Fix More Than Rocky IV Ever Did 

Now, however, it appears that Lundgren has no recollection of whether his potent punches really were the cause of Stallone's unexpected trip to the I.C.U. Answering readers' questions in an interview for the The Guardian, Lundgren opens up on a number of subjects, including his bust-up with Jean-Claude Van Damme and how the camera-angles in Rocky IV helped him appear to tower over Stallone. But before long, the inescapable point of his role in the star's hospitalization came up, and Lundgren appears unconvinced that it was solely his fists that caused the incident:

I don’t know. He keeps talking about it, so maybe he’s right. He did go to the hospital, but I don’t know whether it was my punches or the fact that he was so overworked as the director, actor and writer. We shot those 15 rounds over two or three weeks, eight or 12 hours a day, so you’re throwing thousands of punches. If you don’t connect, it looks a bit fake, but it doesn’t mean you want to hurt the other guy. But there were no hard feelings.

Rocky faces Drago in the ring

Lundgren goes on to admit that he didn't use a stand-in for Rocky IV, having done his own stunts for most of his career, and highlights his continuous need to either be physically fit or "look fit, at least" for his roles. Indeed, it was Lundgren's extraordinary build that convinced Stallone to cast him. To this day, the actor still holds the rank of 4th dan black belt in Kyokushin karate, so the punches he dealt Stallone would certainly have been heightened with a precision and intensity that would otherwise have been absent in almost any other actor. It may not, therefore, be inconceivable that Lundgren's martial-arts expertise alone sent Stallone to the hospital, although his point of the director's overworked schedule also influencing his physical health is certainly plausible.

Whilst the on-screen opponents may differ regarding the exact causes of Stallone's hospitalization, fans will be reassured that it's clearly caused no animosity between the two actors. The pair are set to reunite once again in The Expendables 4, and it seems that Lundgren may reprise his Drago role yet again for an upcoming spinoff following his return in Creed II. So, even though Stallone maintains that Lundgren was the primary cause of his sudden trip to St. John's Hospital, it hasn't put him off working with the actor time and time again, which may well be as strong a testament to their friendship as Rocky IV aficionados could hope for.

More: Sylvester Stallone's Original Concept For Drago Was Very Different (& Worse)

Source: The Guardian