Following NBC’s abysmal February sweeps performance, Jay Leno skewered his network in The Tonight Show monologues. According to a post tonight on the New York Times website, NBC’s Bob Greenblatt took issue with Leno over his televised jabs that followed the network’s fifth-place showing behind Spanish-language network Univision. NBC tonight had no comment on the report that said Greenblatt emailed Leno to complain and the disagreement escalated. Unidentified execs cited in the NYT report said Leno was surprised and pointed to the long-standing tradition of late-night hosts going back as far as Johnny Carson taking jabs at their network masters. Leno’s jokes were pointed. “For the first time in history NBC is going to finish fifth in the ratings period,” Leno said. “We are behind the Spanish-language network Univision — or as we call it here in Los Angeles: Cinco de Ratings.” And later he added, “It’s so bad, ‘The Biggest Loser’ isn’t just a TV show anymore; it’s our new motto.”

Greenblatt’s purported disagreement with Leno was followed by published speculation — vigorously denied by NBC — that the network was planning  to replace Leno with Jimmy Fallon.

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