Minus "Friends" (search) or any big breakout hits, NBC (search) has stumbled out of the starting gate this TV season.

The once proud peacock lost again last week in the only ratings battle it cares about, among the 18-to-49-year-old demographic that advertisers seek, Nielsen Media Research said Tuesday.

That makes four losses in four weeks of the new TV season. It's an unaccustomed spot for NBC, which dominated this demo for the last four seasons, and eight out of the last nine, and has taken in the most advertising revenue as a result.

It's still early, but NBC ranks third this fall behind CBS and a resurgent ABC among all viewers and among the youthful demographic.

"They've lost some of their core properties and now they have to struggle the way everyone has to struggle when they lose their core properties," said Stacey Lynn Koerner, a television analyst for Initiative Media. The last episodes of "Friends" and "Frasier" aired in May.

Matt LeBlanc's new "Joey" (search) is the classic good news-bad news case for NBC.

With its 13.4 million viewers last week, it was television's third most popular sitcom behind "Everybody Loves Raymond" and "Two and a Half Men." It's the top-rated new sitcom.

Yet the "Joey" ratings are 34 percent off what "Friends" was doing at the same point last year. Combine that with a 14 percent drop for "The Apprentice" and longtime hit "ER" now losing its time slot to CBS's "Without a Trace," and you've got some problems on Thursday, traditionally television's most profitable night.

Other networks' hits have also taken their toll on NBC. The network shelved its new drama "Hawaii" after it tanked in the same time slot as ABC's hit "Lost." NBC is moving another new show, "LAX," into that slot.

Meanwhile, "Law & Order" is down 21 percent in the ratings now that it is competing against CBS's "CSI: NY." ABC's "Desperate Housewives," the season's biggest freshman hit with 20.9 million viewers Sunday, has caused the ratings to fade for NBC's "Law & Order: Criminal Intent."

NBC is down 8 percent from last year among all viewers, and 10 percent among viewers aged 18 to 49, while ABC and CBS is up in both categories, Nielsen Media Research said.

"I can't tell you we're clicking our heels up," said NBC Entertainment President Kevin Reilly. "This is tough, and it has gotten tougher with ABC's performance. We're not shocked by our own performance and we've got a job to do to get back up."

NBC is "not doing any worse than we expected them to be," said Steve Sternberg, television analyst for ad buyers Magna Global. "We expected them to be down. The surprise is how well ABC is doing."

It's ABC that has the water-cooler shows, even though NBC had three weeks of Olympics to promote its new programming. With the exception of "The Apprentice" earlier this year, the buzz hasn't been following NBC often enough.

"It's been a slowly building situation," Koerner said, "and there's a lot of pressure on them to come up with something that will work."

On the bright side, the pilot episode for "The Office" — expected in midseason — is hilarious, she said. NBC also has high hopes for some of its reality programming, like "The $25 Million Hoax," which has a woman lying to her family about winning a lottery.

NBC is also high on two drama series in the works. "Medium" stars Patricia Arquette and "Revelations," with the premise of the Biblical warning about the end of the world coming true, should be as big an event as ABC's "Lost," Reilly said.

In a week where baseball's postseason boosted Fox, CBS averaged 12.9 million viewers (8.5 rating, 14 share), Fox had 11.8 million (7.7, 12), NBC 10.2 million (6.7, 11), ABC 10 million (6.5, 11), the WB 4 million (2.6, 4), UPN 3.7 million (2.5, 4) and Pax TV 490,000 (0.3, 1).

NBC's "Nightly News" won the evening news ratings race, averaging 10 million viewers (7.6, 14). ABC's "World News Tonight" had 8.9 million viewers (6.9, 13) and the "CBS Evening News" had 6.9 million (4.9, 10).

A ratings point represents 1,096,000 households, or 1 percent of the nation's estimated 109.6 million TV homes. The share is the percentage of in-use televisions tuned to a given show.

For the week of Oct. 11-17. the top 10 shows, their networks and viewerships: "CSI: Crime Scene Investigation," CBS, 28.9 million; "CSI: Miami," CBS, 21.9 million; "Desperate Housewives," ABC, 20.9 million; "Without a Trace," CBS, 19.4 million; "Survivor: Vanuatu," CBS, 19.2 million; "Lost," ABC, 18.2 million; "Everybody Loves Raymond," CBS, 18 million; "Two and a Half Men," CBS, 17.2 million; "ER," NBC, 16.8 million; "60 Minutes," CBS, 16.5 million.