One of the people who played a key role in getting "Heroes" on NBC's schedule last fall is no longer with the network.

As previously reported, Kevin Reilly left his position as NBC Entertainment president to have the network's creative decisions taken over by producer Ben Silverman. However, in an added twist, the network also appointed NBC Universal executive Marc Graboff as a "co-chairman," who will handle the network's business and marketing components.

"This is a wonderful opportunity for us to capitalize on Ben's creative talents and unique vision and Marc's executive leadership skills," said NBCU chief executive officer Jeff Zucker in a memo sent to network staff obtained by TelevisionWeek.

Silverman was instrumental in bringing both "The Office" to NBC and "Ugly Betty" to ABC through his production company, Reveille, which also had its first-look deal with NBC extended for another two years at the same time.

"This new role will give him the opportunity to redefine our programming, our relationship with advertisers, and our ongoing commitment to the new digital frontier," Zucker said in a later press release announcing the changes.

Reilly has suffered some serious setbacks since signing a three-year extension to stay with NBC last February. Few shows remained on NBC's fall schedule from the previous year, and those that did -- including "Heroes" -- were considered just mild success, or shows like "Friday Night Lights" or "30 Rock," which were considered "on the bubble" of cancellation. NBC finished in fourth place overall for the past season, including a couple weeks that recorded its lowest viewership ever.

Once news started to surface that the network was courting Silverman, Reilly apparently asked to be released from his contract, which NBC granted.

"I grew up watching NBC and have always loved this network," Silverman said in a release. "So this is a dream job for me. And what a thrill it is to be partnering with Marc. We have had great success across the table from each other and I can't wait to be working side-by-side with him to help shape NBC's future during this time of incredible excitement and unprecedented change."

Despite the change at the top of the network, the fall lineup of NBC shows is expected to continue including the new David Eick remake of "The Bionic Woman."