Your first day at a new job is always nerve-wracking — but for Jordan Klepper, joining The Daily Show came with a very public twist. Appearing on The Tonight Show Tuesday, Klepper revealed how his nerves led to a hilariously awkward moment with Jon Stewart that ended up in his debut segment.

Thrown Into the Deep End

Klepper had only auditioned for The Daily Show four days earlier when he was suddenly needed for a segment about Russia invading Crimea. There was just one problem: “Immediately I’m like, ‘What is Crimea? Is it a thing? Is it a place? Where is it?’” he recalled.

When he met with Stewart, Klepper quickly realized he was out of his depth. Stewart, of course, knew the topic inside out, having written editorials and formed strong opinions on it. Klepper, meanwhile, had to figure out how to make it work.

The “Dad” Incident

In the writing process, both Klepper and Stewart threw out ideas to see what would stick. But in a moment of pure nervousness, Klepper accidentally called Stewart “dad.”

“I think I wanted, at that point, to make dad happy!” Klepper laughed. The team decided to run with it — and it became the first joke he ever got on the show.

Stewart’s Last-Minute Advice

Before Klepper took the stage for his first segment, Stewart offered him a bit of blunt, sage advice: “Don’t f—k up.”

The Bottom Line

What could have been a terrifying rookie mistake instead became a defining, on-air moment for Klepper — and a story he’s still telling years later. It’s proof that sometimes, even your most awkward slip-ups can lead to your first big win.