Is it possible to confirm something without actually confirming it? If so, Vin Diesel should teach a master class. The actor has been teasing a mysterious role in a Marvel Studios film since June, and just this week posted an image of Groot from Guardians of the Galaxy on his Facebook page.

After attempting to sidestep a question at Comic-Con International about a potential Marvel collaboration, Diesel was a little more forthcoming Tuesday at a Hollywood Foreign Press Assocation luncheon.

When asked by Hero Complex why he wanted to play Groot, he said, "I’m an actor. I can do whatever the … I want. As an actor, not everything has to be the most obvious choice. And sometimes, the best thing you can do — as far as Steven Spielberg and his advice — is to defy expectations. So if everybody thinks you’re going to go for this one thing and you flip it entirely and go for the strangest Marvel character, it’s interesting. And when something is interesting, it’s inspiring."

"I get inspired by things," Diesel said, referring to the Groot image on his Facebook page. "So if somebody sends me a book of conceptual art that’s the best character design work I’ve ever seen — I’m not kidding, I see that and I want to be a little cryptic and I want to say something positive. Even if it’s as cryptic as an old, dated image of a character."

After explaining that Marvel isn't mad at him for being so open about their dealings, he talked about being a part of a movie that's supposedly halfway done with filming. "I’m so busy," he said. "The audience wanted Vin and Marvel, Vin and Marvel. But I’m too busy to do a six-month role. So what Marvel came up with was really interesting. … I am watching a social wave influence and in some ways guide their thinking."

Directed by James Gunn, Guardians of the Galaxy stars Chris Pratt as Peter Quill, aka Star-Lord, Zoe Saldana as Gamora, Dave Bautista as Drax the Destroyer, Lee Pace as Ronan the Accuser, Michael Rooker as Yondu, Karen Gillan as Nebula, Djimon Hounsou as Korath, Benicio del Toro as The Collector, John C. Reilly as Rhomann Dey, and Glenn Close as Nova Prime. It opens Aug. 1, 2014.