Fourth-place NBC, suffering one of its worst springs in the network's history, fired chief entertainment executive Kevin Reilly Tuesday only three months after giving him a new three-year contract.

Reilly was replaced by the two-man team of Ben Silverman and Marc Graboff. Silverman owned a production company responsible for bringing shows like "The Office" and "Ugly Betty" to American television, while Graboff has been a veteran TV executive concentrating primarily on the business side.

Despite developing "Heroes" and receiving critical praise for shows like "Friday Night Lights," Reilly had been unable to stop NBC's long slide from the heyday of "Friends" and "Seinfeld."

The network had two of its least-watched weeks in memory in April, and watched from the sidelines as Fox's "American Idol" and ABC's "Grey's Anatomy" generated heat in May.

The firing comes at an awkward time for parent company NBC Universal, less than two weeks after NBC released a new fall schedule to lukewarm response and just as NBC is preparing to sell commercial time for next fall.

Silverman founded Reveille Productions, which specialized in adapting ideas for overseas television for American audiences. He played a role in series like "Who Wants to Be a Millionaire," "Big Brother" and "The Biggest Loser."

Silverman and Graboff will both be responsible for all of NBC's prime-time, daytime and late-night programming. Both will report to NBC Universal President Jeff Zucker, although it wasn't immediately clear how they would divide their duties.