During a Reddit AMA with Marvel Studios EVP of Production and Captain Marvel Producer Victoria Alonso, a fan asked about the appearance of actor Patrick Brennan. Brennan played the bartender at Pancho's Bar, where Captain Marvel's Carol Danvers stopped to recollect her memory. As it turns out, Brennan also appeared on Agents of S.H.I.E.L.D. as Marcus Daniels, aka Blackout, who used his Dark Force powers to kidnap Coulson's love interest.
"You noticed?" Alonso replied, suggesting she was aware of the connection.
Brennan made his Agents of S.H.I.E.L.D. debut five years ago in "Providence," the 18th episode of Season 1. After a lab accident, Daniels gained the ability to generate Darkforce and absorb energy, earning him the name Blackout. The accident also drove Daniels insane, to the point where he began to stalk Audrey Nathan, the cellist Coulson was dating in The Avengers. After he broke out of the Fridge, Daniels sought Nathan, who acted as bait so that S.H.I.E.L.D. could draw him out and capture him. The episode ended with his demise.
However, seeing as Captain Marvel takes place in the 90s, the film's nameless bartender could easily be retconned as Marcus Daniels. Perhaps the lab assistant had fallen on hard times, before he found the position that would lead him to become a supervillain in his own right.
Directed by Anna Boden and Ryan Fleck, Captain Marvel stars Brie Larson as Carol Danvers, Samuel L. Jackson as Nick Fury, Jude Law as Yon-Rogg, Clark Gregg as Phil Coulson, Lee Pace as Ronan the Accuser, Djimon Hounsou as Korath the Pursuer, Gemma Chan as Minn-Erva, Ben Mendelsohn as Talos, Lashana Lynch as Maria Rambeau, Algenis Perez Soto as Att-Lass, McKenna Grace as a young Carol Danvers and Annette Bening as the Supreme Intelligence. The film is now available on Digital HD, and it arrives on Blu-ray and 4K UHD on June 11.