The connection between Dustin Hoffman in the bathtub in the movie "Marathon Man" and Jeff Bridges (as The Dude) in the Coen Brother's film "The Big Lebowski."
Marathon Man, starring Dustin Hoffman and Lawrence Olivier as a Nazi war criminal, created a sensation when it was released in 1976. The thriller was directed by John Schlesinger and features Roy Scheider, William Devane and Marthe Keller in supporting roles.
Joel and Ethan Coen wrote and directed the 1988 comedy "The Big Lebowski" which stars Jeff Bridges along with John Goodman, Steve Buscemi, and Sam Elliott, and Julianne Moore.
(Audio excerpted from the "They Shoot Films" Podcast Episode 12: https://www.theyshootfilms.com/marathon-man/)