NBC notched a ratings win Tuesday night, but it wasn’t all roses for the network. “The Voice” was down three-tenths of a ratings point from Monday’s premiere with a 3.9 average rating in the key 18-49 demo, according to Nielsen overnights reported by TVbytheNumbers.com, while the new show “Go On” was well off from its Olympics-boosted premiere with a 3.4, down from the 5.6 delivered by the debut episode.

The second episode of NBC’s “The New Normal” provided some good news, matching the previous night’s 2.5 average in 18-49 for the premiere, but “Parenthood” debuted for season four with a 1.9 — the show’s lowest-rated premiere ever.

It was enough for an easy win for the night by NBC, on a night when CBS and ABC aired all repeats. The Peacock’s only real competition, Fox, settled for a 1.5 average in the 18-49 demo for a two-hour “So You Think You Can Dance.”

For the night, NBC averaged 2.9 in viewers 18-49, ahead of Univision (1.6 average), Fox (1.5), CBS (1.2) and ABC (0.7). NBC’s margin in total viewers was narrower, with an average of 8.4 million to lead CBS (7.5 million), Fox (4.3 million), Univision (3.5 million) and ABC (2.4 million).