The countdown is on for Avengers: Doomsday, the next massive installment in the Marvel Cinematic Universe, which hits theaters in December. Marvel has already confirmed that Robert Downey Jr. will return to the franchise as Doctor Doom — and now the studio has surprised fans with an unexpected promotional move.

Through a partnership with Major League Baseball, Marvel produced a film-specific promo video. Decorated with baseball-themed touches, the short clip offers a small but eye-catching preview of the movie's tone.

The premiere took place at the ballpark

The video debuted during the first game of the series between the Tampa Bay Rays and the Milwaukee Brewers. In the footage, Pedro Pascal, who plays Mister Fantastic, captain of the Fantastic Four, takes the field for the ceremonial first pitch, and is greeted at the stadium by Joseph Quinn, who plays the Human Torch.

The clip then cuts to footage from the film itself. Steve Rogers back as Captain America, Robert Downey Jr.'s Doctor Doom, Thor, Ant-Man and a host of other characters all appear in the brief teaser.

A star-studded cast

Like previous Avengers films, Doomsday carries an extensive roster of names. The cast includes Robert Downey Jr., Chris Evans, Pedro Pascal, Chris Hemsworth, Joseph Quinn, Vanessa Kirby, Ebon Moss-Bachrach, Tenoch Huerta, Simu Liu, Letitia Wright, Danny Ramirez, Winston Duke, Anthony Mackie, Sebastian Stan, Patrick Stewart, Ian McKellen, Kelsey Grammer, Alan Cumming, Rebecca Romijn, James Marsden and Channing Tatum.