LOS ANGELES – With a supporting role in Marvel’s Guardians of the Galaxy Vol. 2, veteran action star Sylvester Stallone has pretty much checked all the boxes.

“The only thing I haven’t done is perform brain surgery on myself,” he told the Sun with a laugh at a recent press day for the sequel at a West Hollywood hotel.

“I’ve been very, very lucky and you know, I’ve spared Shakespeare undue stress by not doing that because, ‘To be or not to be,’” he continued dipping into Rocky-speak, “I don’t think it works.”

It’s been over 20 years since Stallone’s last foray into the cinematic realm of comic books (he appeared in 1995’s Judge Dredd). For most of the aughts, Stallone pumped out standard action fare, as well as updates in his Rocky and Rambo series and a new franchise – The Expendables.

But the Marvel Cinematic Universe was something completely different to the 70-year-old.

“It’s one thing to do the kind of action movies I do, but there’s a lot to (Guardians of the Galaxy) and I was very, very impressed by the patience and professionalism and just the overall skill set that these people possess. I’m jealous.”

Stallone plays Stakar Ogord, a.k.a. Starhawk, one of the original Guardians of the Galaxy and former friend of Yondu (Michael Rooker), who he exiled for stealing children and selling them on the black market.

It’s a small role in a bigger story involving Star-Lord’s (Chris Pratt) relationship with his newly discovered father, Ego (Kurt Russell), but one that Guardians writer-director James Gunn promises will get bigger in future MCU films.

“My plan is to see more of him,” director James Gunn told the Sun in a separate interview. “I’m not sure about him appearing in Vol. 3, we’ll have to see about that, but it’s our plan to see more of Stallone. (Marvel studio boss) Kevin (Feige) and I are working on what is going to become of the Marvel Cosmic Universe and where it’s going to go. We plan to see the rest of them in the future.”

The “them” Gunn is referring to is the original Guardians crew, which includes Aleta Ogord (Michelle Yeoh), Charlie-27 (Ving Rhames), Krugarr (a CG character), the Miley Cyrus-voiced Mainframe, as well as Stallone’s Starhawk and Michael Rosenbaum’s Martinex.

“They’re definitely the original Guardians,” Feige added. “Where we see them in the future, time will tell.”

Stallone is intrigued to be a continuing part of the MCU because he sees these characters as heroes for a new generation.

“Early on in my career, I just always became fascinated with mythology and Joseph Campbell (and his book The Hero with a Thousand Faces). When I started doing Rambo, (I came to understand) there’s an evolution that takes place. Each generation has to define itself and find its own heroes and its own mythology and (the MCU) is this generation’s and maybe the next generation’s mythology.

“When Kevin invited me on board I said, ‘This is interesting because I haven’t gone here.’ I’m kind of earthbound. ... This is something that takes place in a whole other sphere where James and the Marvel people have created their own world, their own reality. So I said, ‘Let me drop in here and see what’s up.’”

Stallone, who jokingly referenced ‘60s Silver Age hero Elastic Man as a character he was familiar with, didn’t know much about the Guardians going into the film. But he’s catching up on the comic book storylines now.

“Because I’m an optimist,” he laughed.

Besides, being part of the MCU is a heck of a lot easier than dodging bullets as Barney Ross in the Expendables.

“When I walked on the set, you see robots and a woman who is seven-foot tall and I thought it was great. It was a great vacation. It’s better than being up a tree in Burma. You know what I mean? Much better. Trust me.”

Guardians of the Galaxy Vol. 2 opens this Friday.

Twitter: @markhdaniell

MDaniell@postmedia.com