Avengers: Endgame - 20 Things We Learned From The Director's Commentary
18. Captain Marvel Was Almost Revealed A Scene Later
Captain Marvel (Brie Larson) joins Endgame's story surprisingly early on, arriving to rescue Tony Stark when he's on death's door, appearing before him in a brilliant cosmic light before returning him and Nebula to Earth.
But the scene originally played out a little differently, with early cuts of Endgame showing only the light reflecting on Tony's face and not revealing Carol's arrival until she brings the Benatar back to Earth.
The Russos ultimately found in editing that this approach was confusing for the audience, especially as they hadn't shot a close-up of Carol returning to Earth with the Benatar in tow, which would've made the transition smoother.
Joe Russo also confirms the means through which Carol tracked down the ship: there was a homing beacon on The Benatar which allowed Captain Marvel to locate it after first meeting up with The Avengers on Earth.