The character, played by Brie Larson, is thought to be making her MCU arrival in Avengers 4, due next year – before she gets her own solo outing.
But the Super Bowl TV spot, debuted on Sunday night, features a blink-and-you-miss-it appearance from a character who some think is Carol Danvers herself.
There’s a brief moment when Captain America (Chris Evans) and Black Widow (Scarlett Johansson) can be seen with Vision – and someone else in the background.
The suit that figure is wearing seems to have a star-like shape on it – very similar to the iconic one on Captain Marvel‘s.
Twitter user @spideyrogrs, who pointed out the similarity, has had over 2,500 retweets for their observation.
Of course there’s every possibility that, on closer inspection, the two are nothing alike.
In fact, many have suggested that it’s Wanda, the Scarlet Witch – or even Spider-Man in his new suit.
But it’s certainly an exciting proposition to think that, even with a cast as big as Infinity War’s, we could still get a surprise appearance from someone completely unexpected.
What’s also interesting about this particular shot is that it seems to quash speculation that Vision would meet a quick demise as soon as the Mind Stone was removed.
It had previously been said that Larson would not be in Infinity War, after the Russo brothers – the directors – told ComicBook.com fairly definitively last summer: “She’s not in Avengers 3.”
The Infinity War teaser, which followed the full trailer last November, seemed to put Robert Downey Jr’s Iron Man in the spotlight.
The likes of Nebula (Karen Gillan), Loki (Tom Hiddleston), Spider-Man (Tom Holland) and Thor (Chris Hemsworth) were also seen, along with the fearsome Thanos (Josh Brolin).
Avengers: Infinity War is out on April 27 in the UK.