Powerful perfs on Thursday and Sunday accented another impressive weekly victory for NBC, which has all the momentum in the early going of the May sweep.

Penultimate episode of “Friends,” the week’s top show in adults 18-49 (11.2/32), combined with the season finale of “Will & Grace” and a big “ER” (Daily Variety, May 3) to give the net a decisive Thursday victory in adults 18-49. And Sunday’s “10.5,” the top-rated movie of any net in more than two years (8.1/20), closed the week in a big way (Daily Variety, May 4).

Overall for the April 26-May 2 frame, the Peacock dominated in all significant categories, according to Nielsen, including a big 23% advantage over second-place Fox in adults 18-49 (4.8/14 to 3.9/11). Net also led in adults 25-54 (5.4/14) and total viewers (12.1 million).

NBC’s weekly 18-49 average was the best for any network in the nine weeks since ABC scored with the Academy Awards. And by comparison, it was bigger than last week’s primetime scores for the top eight basic cable nets combined.

Through Monday of this week (five nights of the four-week ratings period), NBC led in 18-49 with a 5.5 rating/16 share (up 17% in rating vs. a year ago), followed by CBS (3.8/11, even), Fox (3.1/9, down 3%), ABC (2.6/7, down 7%), the WB (1.4/4, down 7%) and UPN (1.1/3, down 21%).

NBC was also the surprise early leader in total viewers (13.7 million to 13.2 million for CBS).

Elsewhere for the Peacock, “Frasier” notched its best scores in five months (4.5/12 in 18-49, 12.44m) as it nears its finale, and Tuesday’s “Law & Order: SVU” (5.2/13), Wednesday’s “Law & Order” (5.7/15) and Friday’s “Third Watch” (3.2/10) all topped their 10 o’clock hours in 18-49.

Over at Fox, both nights of “American Idol” again ranked in the top five, helping the net extend its long winning streaks on Tuesday and Wednesday. Also clicking on these nights were dramas “24” (5.0/13 in 18-49, matching a season high) and “The OC” (4.7/12 in 18-49) and laffer “That ’70s Show” (4.7/15 in 18-49).

Net also led Saturday in demos, with “America’s Most Wanted” (2.9/10 in 18-49) up 16% vs. its opening-week May sweep score last season.

CBS, third in 18-49 and second in adults 25-54, claimed the week’s most-watched program overall in Thursday drama “CSI” (26.37 million), while skedmate “Survivor: All Stars” (7.5/21 in 18-49, 20.78m) held up well opposite “Friends.”

ABC delivered its best 18-49 score in nine weeks, led by red-hot reality skein “Extreme Makeover: Home Edition” (series-high 5.4/15 in 18-49, 13.15m), as well as the Wednesday reality tandem of “The Bachelor” (5.0/13 in 18-49, 11.62m) and “Extreme Makeover” (4.9/13 in 18-49, 10.67m).

The WB (1.8/6 in adults 18-34) pulled away from a struggling UPN (1.0/3), which has found life difficult after “America’s Next Top Model” ended its season in March.

“Gilmore Girls” and “One Tree Hill” combined for the Frog’s highest-rated Tuesday of the season, and Friday laffers “Reba” and “What I Like About You” led their slots in young femmes.

Among ad-supported cablers, basketball-boosted TNT led in adults 18-49 (1.0 rating), 25-54 (1.1) and 18-34 (1.0) as well as total viewers (2.68 m).

MTV’s “Punk’d” was the frame’s top entertainment program on the basic cablers in both adults 18-49 (1.7/4) and adults 18-34 (2.8/7), while Discovery’s “American Chopper” was tops in adults 25-54 (1.6/5).

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On Monday of the current week, NBC movie “10.5” concluded with nearly identical numbers to its Sunday opener (8.0/20 in 18-49, 19.87m), becoming the first entertainment program to top an original seg of CBS drama “CSI: Miami” (6.3/16 in 18-49, 17.62m).

Peacock also scared up viewers at 8 with “Fear Factor” (5.3/15 in 18-49, 12.32m), which topped a special seg of Fox spec “American Idol: The Final Five” (4.8/14, 11.73m).

CBS was a solid second opposite “10.5” from 9 to 11 with “Everybody Loves Raymond” (5.8/14 in 18-49, 17.27m), “Two and a Half Men” with guest star Heather Locklear (5.8/14, 16.20m) and “CSI: Miami.”

Fox again did pretty well with surgery skein “The Swan” (4.6/11 in 18-49, 10.13m), but ABC bombed with the preem of theatrical hit “Unbreakable” (1.9/5 in 18-49, 5.40m).