Jimmy Fallon, Seth Meyers, John Mulaney mourn NBC executive Rick Ludwin

Stars are paying tribute to late NBC executive Rick Ludwin.

Ludwin, who championed the popular sitcom "Seinfeld," died Sunday. In a statement to Paste BN Tuesday, NBCUniversal Content Studios Vice Chairman George Cheeks confirmed the news.

"Rick left an indelible mark in his 30-plus years at the network, with a rich legacy that lives on to this day," the statement read.

Famed colleagues, including Jimmy Fallon and others, were quick to share their thoughts on Ludwin after the news of his death.

During "The Tonight Show with Jimmy Fallon" Monday the host praised the longtime exec in charge of late night at the network for changing "the face of television."

"I'll never forget how generous he was with his time and advice," Fallon said. "He was just so encouraging... He was also a walking encyclopedia of late night... He knew all these great stories."

Seth Meyers also paid tribute to Ludwin on his show "Late Night," saying he met the "legend" in 2001 when the host joined "Saturday Night Live."

"There was nothing Rick liked more than talking about late night and he was so giving and warm with his history and his stories and his time," he said. "He was kind in a way that was very unique for this world that we live in, in television and the entertainment industry. He will just be deeply, deeply missed."

Comedian John Mulaney shared a lengthy, heartfelt Twitter thread about Ludwin.

"He was kind and thoughtful in an arena where that can be rare. From the day I began at "SNL," he would email me any time he liked a sketch I had worked on. He loved television," he tweeted.

He continued, "We were supposed to get lunch when I played his Alma Mater Miami of Ohio a few weeks ago. But he canceled due to his health. And so no more lunches. 

Anyway... Should anyone tell you that you have to be an (expletive) to make an impact in entertainment, I offer you Rick Ludwin."

Conan O'Brien also tweeted about Ludwin's passing. 

"There is not a single executive in my career that I admire more than Rick Ludwin, and I will not see his like again," he wrote.

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