Ferrell's debut as Deangelo Vickers pulled in 7.7 million (4.6/7) for NBC at 9pm, also securing a 18-49 score of 3.9, the highest for any scripted show last night.
Meanwhile, the latest departure from American Idol netted a round 21m (12.0/20), after which Bones logged 11.9m (7.1/11), leading Fox to victory with a 6.1 score for 18-49 adults over primetime.
The Paul Reiser Show, the eponymous new sitcom, launched with a disappointing 3.3m (2.2/3) for NBC at 8.30pm, behind Wipeout's 6.2m (3.5/6) for ABC. Reiser's chances were not helped by Community's 3.5m (2.2/4) before it.
The rest of the network's comedy output fared slightly better: Parks and Recreation entertained 5.2m (3.2/5) at 9.30pm, 30 Rock amused 4.5m (2.8/5) from 10pm, and Outsourced interested 3.5m (2.2/4) at 10.30pm.
'The Last Dance' in The Vampire Diaries attracted 2.8m (1.8/3) to The CW in the 8pm hour, then another action-packed Nikita instalment fetched 2.2m (1.3/2) at 9pm.
Elsewhere, repeats of The Big Bang Theory, Rules of Engagement, CSI and The Mentalist found respective audiences of 7.5m (4.9/8), 5.8m (3.7/6), 8.2m (5.3/8) and 10.8m (7.0/11), while Grey's Anatomy and Private Practice reruns notched up 4.2m (2.8/4) and 2.9m (2.1/3).