After a fall filled with positive signs for NBC, the Peacock Network has suffered a major blow.

For the first time ever, Univision has so-far edged NBC out of the top four networks during the highly competitive February sweeps period, a time when ratings are traditionally important to networks as they help determine local ad rates. In the first 20 days of sweeps, NBC averaged a 1.2 rating in the 18-49 demo while Univision has averaged 1.5. CBS (*4.9), Fox (2.0), and ABC (1.7) make up the top three so far.

This stat is even more striking considering back in November, NBC was in a dramatically different situation. Last fall, the network saw its first November sweeps victory in nine years, thanks largely to top-performing The Voice, Revolution, Sunday Night Football — all of which contributed to NBC’s 2.9 rating average in the 18-49 demo.

Of course, they never expected to stay on top. Shortly after touting NBC fall victory, Entertainment Chairman Bob Greenblatt said he expected a dip in the second half of the TV season, telling reporters that he would be happy to rank third, but that he was “pretty confident we’re not going to end up in fourth place again this year.” Well, to be fair, they didn’t…

In the last few months, there have been several factors that contributed to the shift. First, NBC saw disappointing debuts from freshman shows Do No Harm, 1600 Penn and Deception and the second season of Smash has hit a low note in ratings. Univision picked up viewers from its continued news and feature coverage of Latin superstar Jenni Rivera’s unexpected death and has also seen strong demo ratings for its telenovelas. (Though, the overall upward track of Univision is something that’s been noted for at least a couple of years, when the network began seeing primetime ratings wins over NBC.)

* Demo average includes Super Bowl and Grammy ratings.