All Around the World entertained 3.3m (0.9) on NBC in the 8pm hour, just over half the 6.2m (1.7) who watched Adele's London gig over three weeks ago.
Dogs in the City dipped to 4.9m (1.0) for CBS at the same time.
Meanwhile, Duets held steady for ABC with 4.2m (1.1) between 9.30pm and 11pm.
So You Think You Can Dance was the most-watched broadcast with 6.5m (2.1) for Fox between 8pm and 10pm.
Overall, Fox won primetime ahead of ABC, CBS, NBC and The CW.