Ascending to the “Tonight Show” host chair under unscrupulous circumstances, Jay Leno might exit the “Tonight Show” via the same way he entered.

The 59-year-old Leno, who has been host of the longest regularly scheduled entertainment program in the U.S. for 20 years has been having “issues” with his employers since joking about the network’s struggles.

"You know the whole legend of St. Patrick, right? St. Patrick drove all the snakes out of Ireland, and then they came into the United States and became NBC executives," Leno joked, as some in his studio audience gasped. "It's a fascinating story, a fascinating story," reported LA Times.

The insult came just days after the New York Times reported that NBC chief Bob Greenblatt traded tense emails with Leno over recent "Tonight Show" jokes ridiculing NBC's poor ratings this winter.

"It's so bad, 'The Biggest Loser' isn't just a TV show anymore it's our new motto," Leno said in late February."It's so bad, NBC called Manti Te'o and asked him to bring in some imaginary viewers," the comic quipped, according to New York Daily News.

Their relation has deteriorated even further, due to a Hollywood Reporter story claiming that NBC is looking for his replacement.

In fact, THR states a formal announcement that “Late Show” host, Jimmy Fallon will replace Leno is planned for May, although the network has denied that's the case.

The logic behind the switch, according to THR, is to try and fend off ABC's Jimmy Kimmel, who recently moved his show to the same time slot as the “Tonight Show.” NBC executives are worried because Kimmel was inching closer to Leno in the coveted 18-34 demographic.

Leno's rep said the host had no comment. Asked if the network wanted to comment on the situation, an NBC spokesman emailed, "No — but appreciate you checking in."