Robin Williams takes Michael J. Fox in their TV premieres

Robin Williams' new CBS comedy, "The Crazy Ones," debuted before 15.6 million people on Thursday night.  "The Michael J. Fox Show" on NBC was seen by 7.2 million people. Robin Williams plays an advertising executive, Fox plays a TV newscaster.

Robin Williams has early bragging rights over Michael J. Fox in the competition between two sitcom veterans returning to network TV — with an asterisk.

The Nielsen company said Friday that Williams' new CBS comedy, "The Crazy Ones," debuted before 15.6 million people on Thursday night. It competed directly at 9 p.m. Eastern with "The Michael J. Fox Show" on NBC, which was seen by 7.2 million people.

Williams, who plays an advertising executive working in a firm with his daughter, had a huge advantage. His new sitcom directly followed a new episode of television's most popular comedy, "The Big Bang Theory," which was seen by 19.5 million people in the second of a two-part season premiere.

By contrast, the second half hour of "Parks & Recreation" on NBC, which preceded Fox's new show, had less than 3 million viewers.

CBS succeeded in getting people to sample Williams' new show by scheduling the extra "Big Bang" episode. Moving forward, however, "The Crazy Ones" will be preceded by another new show, "The Millers," on the schedule.

"I really think you have to sit and wait to see what happens," said Brad Adgate, researcher for Horizon Media.

NBC ran two separate episodes of "The Michael J. Fox Show," where the star plays a newscaster coming back to work with Parkinson's disease, which Fox also suffers from. The second, at 9:30 p.m., had a larger audience of 7.4 million people, Nielsen said.

NBC notes that the audience during that hour was double what the network was reaching on average at 9 p.m. Eastern last year with "The Office" and "Parks & Recreation."

Adgate said there was an expectation that the well-known Fox would attract a bigger audience for his return than he actually did.

"Granted, it's a weak lead-in," he said, "but they put him on the show to create appointment viewing and that didn't happen."

Both shows apparently attracted a lot of the stars' old fans. Adgate said the median age of "The Crazy Ones" audience was 55, while it was 54 for "The Michael J. Fox Show."

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