Rick Ludwin, who oversaw late-night programming at NBC for many years but is probably best known for backing the sitcom “Seinfeld” when it seemed the network might drop the show before it started its storied run, died on Sunday in Los Angeles. He was 71.

His death, at a hospital, was caused by organ failure, said Daniel Ludwin, his nephew.

Mr. Ludwin was in charge of NBC’s late-night shows — including “Saturday Night Live,” “The Tonight Show,” “Late Night With David Letterman” and assorted specials — when he became part of the “Seinfeld” origin story, as it evolved from a possible one-time 90-minute special to fill in for “S.N.L.” into a weekly series, about four misanthropic friends in Manhattan.

In the beginning, at screenings of the pilot for what was then called “The Seinfeld Chronicles,” created by Jerry Seinfeld and Larry David, audiences were underwhelmed.

“The test audiences felt the supporting cast was not strong enough and Jerry himself was a weak lead,” Mr. Ludwin said in “Seinfeld: How It Began” (2004), a documentary that was part of a “Seinfeld” DVD release .