Various NBC dayparts have seen a halo effect in the ratings during the net’s coverage of the Olympics, and that is especially true for “NBC Nightly News,” which hit a nine-year high last week.

Anchored by Brian Williams from the site of the Winter Olympics, “Nightly News” averaged 11.61 million viewers, according to Nielsen — outperforming the opening week of the past four Olympics. This put it nearly 2.8 million viewers ahead of ABC’s “World News With Diane Sawyer” (8.84 million), which had trailed in the comparable week during the 2010 Winter Olympics by more than 3 million, and about 3.7 million ahead of the “CBS Evening News With Scott Pelley” (7.95 million).

Overall, it’s the largest average crowd for the NBC newscast since January 2005. In the most recent Olympics years, the program’s first week drew 10.8 million from London in the summer of 2012 and 11.1 million from Vancouver in 2010.

“Nightly News” also dominated in adults 25-54 (2.7) over “World News” (2.0) and “Evening News” (1.8).

NBC, of course, has been doing huge numbers in latenight with the “Tonight Show” transition from Jay Leno to Jimmy Fallon. And last week saw the net’s morning program “Today” score a rare victory over ABC’s “Good Morning America.”

For “Nightly News,” it certainly has helped having Williams hosting live from the Olympic Park in Sochi, Russia.  Tune-in was especially high on Monday and Tuesday, with both telecasts drawing more than 12 million viewers.

Despite the strong showing by “Nightly News,” ABC’s “World News” improved on its performance of a year ago for the fourth straight week. The Alphabet program is enjoying its most-watched season in five years and its strongest in the demo in three years, enjoying its closest position to NBC’s newscast in six years.

“CBS Evening News” also posted year-over-year gains in both the 25-54 demo and total viewers.