Guardians of the Galaxy Vol. 2 wrapped principal photography in Atlanta and is currently in post-production with plenty of time before the film opens the summer 2017 movie season with a May release date. While it has yet to be announced, Guardians of the Galaxy 3 is arguably the safest bet of any of the untitled 2020-21 movies Marvel Studios has already scheduled for Phase 4 of the Marvel Cinematic Universe.

It's no secret that fans will get to see the Guardians in between the two installments however, since they will have a part in Avengers: Infinity War, a title that previously represented both entries of a previously announced two-part event movie, releasing in 2018 and 2019. That has since changed with Avengers 3 solely taking the subtitle of "Infinity War" and thanks to the voice of Groot (Vin Diesel) we can confirm that the Guardians of the Galaxy will indeed be in that first 2018 Avengers movie.

In a Facebook live stream, Vin Diesel - who has the single most popular page on the platform with over 100 million followers - spoke again about being grateful to fans (in light of recent events between a reported feud between him and The Rock on the set of Fast 8) and continued to hype up the upcoming xXx: Return of Xander Cage, but also teased what fans have been waiting for: The Avengers meeting Marvel's Cosmic Avengers, the Guardians of the Galaxy.

"Next year you've got Guardians of the Galaxy Vol. 2 coming and that whole concept started from you all saying 'when are you gonna be in a Marvel movie?' And you remember the first picture after that Marvel meeting that I had where I was standing [with] the Avengers thing in the back - some of you can look up that picture...there was this old Avengers copy that was behind me in that picture if you look back on my Facebook page you can find that.

What's gonna be surreal is that picture is going to come to pass because now the Guardians will be included in Avengers: Infinity War and that's incredibly exciting. Incredibly exciting. Incredibly exciting and something that if you were a part of our page you knew before everybody."

The photo Diesel's referring to was from July 9, 2013, taken within Marvel offices:

And since then, the actor/producer has shared numerous shots of Groot or of him standing beside the Hulk - so count on each team's "muscle" finally having the chance to meet each other on screen in a few years. It's not a surprise given that Avengers 3-4 directors Anthony and Joe Russo, along with writers Christopher Markus and Stephen McFeely, have been openly discussing their excitement over using the Guardians of the Galaxy characters but now we can say for certain they most definitely will be involved in both Avengers: Infinity War and whatever they end up naming Avengers 4 (our ideas here).

And you can count on Captain Marvel showing up too!

More: Guardians of the Galaxy 3 On the Way

Starring Bradley Cooper, Chris Pratt, Chris Sullivan, Dave Bautista, Elizabeth Debicki, Glenn Close, Karen Gillan, Kurt Russell, Michael Rooker, Nathan Fillion, Pom Klementieff, Sean Gunn, Sylvester Stallone, Tommy Flanagan, Vin Diesel, and Zoe Saldana.

Doctor Strange opens November 4, 2016; Guardians of the Galaxy Vol. 2 – May 5, 2017; Spider-Man: Homecoming– July 7, 2017; Thor: Ragnarok – November 3, 2017; Black Panther – February 16, 2018; Avengers: Infinity War – May 4, 2018; Ant-Man and the Wasp – July 6, 2018; Captain Marvel– March 8, 2019Avengers 4 – May 3, 2019; and as-yet untitled Marvel movies on July 12, 2019, and on May 1, July 10, and November 6 in 2020.

Source: Vin Diesel