It might seem the two men who both served at Captain America's side would be natural friends, but a clip from the upcoming The Falcon and the Winter Soldier series on Disney+ instead showcases the palpable tension between them.

The clip posted Friday on Marvel Entertainment's YouTube channel opens with a long moment of glaring silence between Bucky Barnes' Winter Soldier, played by Sebastian Stan, and Sam Wilson's Falcon, played by Anthony Mackie, as they ready for an unknown mission. As Sam prepares for an air drop, Bucky asks, "What's the plan?" only to be met with more silence.

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"Great," Bucky responds. "So no plan."

After a few more hushed seconds, Sam tells Bucky, "Enjoy your ride, Buck," -- a name Bucky doesn't appreciate being called by Sam.

"Nah, you can't call me that," Bucky retorts. "Why not?" Sam queries, "That's what Steve called you."

"Steve knew me longer, and Steve had a plan."

"I have a plan," Sam concedes, before jumping out of the airborne transport. But clearly he doesn't want Bucky in on it.

The reason for the tension isn't clear, although it's possible that Bucky might harbor some resentment over Steve Rogers handing over the mantle of Captain America to Sam at the end of Avengers: Endgame, rather than to him. Interestingly, though, it seems that Sam might not be the new Cap after all, as seen in another clip from the series.

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Bucky served with Cap during World War II in Captain America: The First Avenger, but was seemingly killed in action, until Captain America: The Winter Soldier revealed he had survived. Sam became Cap’s modern-day crimefighting partner in the latter film.

By way of the two characters speaking of Steve in past tense, the new video seems to confirm what had been long suspected by fans -- that Steve has in fact died after the events of Endgame. The loss of their mutual friend and mentor could also be causing some frazzled emotions between the two allies.

As of Endgame's epilog, the story of Steve Rogers' life had been told, so his passing would be the most efficient and poignant way to write his character out of the Marvel Cinematic Universe.

Directed by Kari Skogland, The Falcon and the Winter Soldier stars Anthony Mackie, Sebastian Stan, Emily VanCamp, Wyatt Russell, Noah Mills, Carl Lumbly and Daniel Brühl. The series premieres March 19 on Disney+.

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Source: YouTube