HBO’s "Friends: The Reunion" special features a wide list of guest stars, but Paul Rudd and Cole Sprouse were notably missing.

The two actors were supporting characters who played alongside the six main cast members: Jennifer Aniston, Courteney Cox, Matthew Perry, Lisa Kudrow, David Schwimmer and Matt Leblanc. However, the reunion special’s director, Ben Winston, told The Wrap there was a reason why Rudd and Sprouse weren’t included.

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"Well, we couldn’t have everybody on, because it’s only an hour and 45 minutes. And you’ve got to pay attention — the main nub of the show has got to be about the six cast members," Winston told the entertainment news outlet. "So you can’t have too many cameos because of course, there were hundreds of amazing people who were in ‘Friends’ over the years. Sadly, we couldn’t get everybody in."

Some of the guest stars who did appear in the 105-minute program for HBO Max had supporting cast roles in the NBC sitcom, including Reese Witherspoon, Larry Hankin, Thomas Lennon, Christina Pickles, Tom Selleck, James Michael Tyler, Maggie Wheeler and Elliott Gould.

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The rest of the special’s guest stars weren’t involved with the show, but all were fans of the series, including David Beckham, Justin Bieber, BTS, James Corden, Cindy Crawford, Cara Delevingne, Kit Harington, Lady Gaga, Mindy Kaling and Malala Yousafzai.

While Winston shared a reasonable explanation for the absence of certain characters, a fair number of HBO Max subscribers shared their disappointment on social media.

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"That Friends Reunion was so cute," Brooklyn Blerd writer Ashley K. Smalls wrote Thursday evening. "I wish they could’ve gotten Paul Rudd and Cole Sprouse too."

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Meanwhile, Rolling Stone Associate Editor Angie Martoccio offered their critique Friday morning.

"The Friends reunion: ‘We simply do not have the time to include Paul Rudd and Cole Sprouse, but we MUST feature Justin Bieber in a potato suit,’" Martoccio tweeted.

Rudd, 52, played the role of Kudrow’s onscreen husband Mike Hannigan. The actor is currently filming the third installment of Marvel’s "Ant-Man" film franchise, according to IMDb.

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Sprouse, 28, was Schwimmer’s onscreen son Ben Geller. Sprouse isn’t currently filming, but he is a main cast member of the CW’s "Riverdale" series, which is in its fifth season. His IMDb page says he’ll be appearing in two upcoming projects named "Undercover" and "Moonshot."