CHICAGO (thefutoncritic.com) -- Viewers hoping to catch a new episode of NBC's "The West Wing" last night got a surprise: a repeat of "Law & Order: Criminal Intent" instead. A previously announced new installment of "Law & Order" was also bumped in favor of a repeat of last season's finale. So why is the Peacock all of a sudden in repeats despite the season being only three weeks old?

While NBC has yet to comment on the change, all signs point to a better than expected turnout this season for the MLB League Championship Series on FOX. Last night's conclusion to the NLCS featuring the Chicago Cubs and the Florida Marlins drew a monster 15.5 rating and 24 share in households and a 9.3 rating in adults 18-49, according to fast national data, more than double NBC's average for the night (second place 7.5/12 in households, third place 3.7 in adults 18-49). Compared with last Wednesday, NBC was down 13% in households and 16% in adults 18-49.

Such a performance has caused NBC to bump next week's new episodes of "The West Wing" and "Law & Order" as well when the duo would have faced Game 4 of the World Series. Lead-off drama "Ed" however, like last night, will still continue with a first-run episode next week.

Furthermore with the ALCS set for Game 7 tonight, NBC will dump its planned new episodes of "Friends," "Scrubs," "Will & Grace" and "ER" in favor of repeats of the quartet.

To review, here's a list of the schedule changes in store for NBC:

Thursday, October 16:
8:00/7:00c - "Friends: The One With Ross's Inappropriate Song" (Repeat)
8:32/7:32c - "Scrubs: My Big Brother" (Repeat)
9:00/8:00c - "Will & Grace: Women and Children First" (Repeat)
9:30/8:30c - "Whoopi: The Vast Right Wing Conspiracy" (Repeat)
10:00/9:00c - "ER: The Advocate" (Repeat)

Wednesday, October 22:
8:00/7:00c - "Ed: Death, Debt & Dating" (New Episode)
9:00/8:00c - "The West Wing: Red Haven's on Fire" (Repeat)
10:00/9:00c - "Law & Order: Couples" (Repeat)

NBC will then resume with new episodes of all three of its Wednesday dramas on October 29. It's not clear however if NBC's Thursday lineup will resume new installments on October 23 should the World Series go to Game 5.

Bumping first-run episodes for repeats at the last minute when facing stiff competition isn't something new. Last season when the World Series went to Game 7, ABC ditched new episodes of its Sunday dramas "Alias" and "The Practice" in favor of repeats of the duo without warning.

Late update (5:35 PM): CBS has also decided to yank the majority of its Thursday lineup tonight. Both "C.S.I." and "Without a Trace" will run repeats instead of their previously announced first-run episodes. "Survivor" however will still be a new episode at 8:00/7:00c. The remaining broadcast networks (ABC, UPN and the WB) still plan to stick with their original schedules at the time of this writing.