Las Vegas Week kicked off with 10.4m (3.0) in the 9pm hour, moved from its usual 8pm slot.
However, the episode lost 800k viewers on last week's instalment, preliminary Nielsen overnight data shows.
Live Olympic Trials filled the Peacock Network's 8pm junction, securing a respectable 7m (1.9).
Meanwhile, a shorter American Ninja Warrior took 6.1m (2.0), matching last week's two-hour special.
Elsewhere, Hell's Kitchen (5.5m/2.3) and MasterChef (5.4m/2.2) fell slightly for Fox.
The Bachelorette was fairly steady for ABC with 7m (2.2) between 8pm and 10pm, then The Glass House sunk to 3.3m (1.2).
CBS and The CW screened wall-to-wall reruns and predicably finished below the Alphabet Network.