Paul McCartney can’t let one element of the upcoming Beatles biopics be. 

After Paul Mescal was announced to play the “Hey Jude” hitmaker in Sam Mendes’ forthcoming project The Beatles—A Four-Film Cinematic Event, McCartney admitted he had one qualm with the casting. 

“I said, ‘Sam, I’ve got just one thing that I need to say to you. You know, Paul’s a bit small,’” McCartney told Amy Poehler on the Oct. 13 episode of her Good Hang podcast. “I texted him, ‘Sam! Smaller! Don’t do this, you said you wouldn’t do it!’”

Indeed, it was after the 84-year-old saw a photo of the cast—which also includes Harris Dickinson, Barry Keoghan and Joseph Quinn as John Lennon, Ringo Starr and George Harrison, respectively—recreating the band’s iconic cover for their 1969 album Abbey Road, which sees the musicians walking along a crosswalk, when McCartney realized the height difference. 

Although the Skyfall director quickly set to ease the music icon’s fears. 

“He said ‘No, it’s okay, it’s just the stride pattern,’” McCartney recalled of his conversation with Mendes. “He sent me another one where they were equal.”