The final Thursday before the start of the May sweep was a good one for CBS, whose “The Big Bang Theory” was again the night’s top-rated show while “The Odd Couple,” “Mom” and “2 Broke Girls” matched or set season highs. One of the possible reasons for the middle-hour comedy gains for the Eye was another downtick for ABC’s “Scandal,” which appears to have hit a series low.

According to preliminary national estimates from Nielsen, “The Big Bang Theory” (3.1 rating/12 share in adults 18-49, 13.8 million viewers overall) was easily the night’s top show, and figures to finish up a little in both categories from its prior original of two weeks ago. “The Odd Couple” followed at 8:30, improving its renewal chances with season highs (1.7/6 in 18-49, 8.6 million viewers overall), up 0.2 from last week (when it had a “Big Bang” repeat lead-in) and two weeks ago (with a new “Big Bang” behind it).

“Mom” (1.8/6 in 18-49, 8.4 million viewers overall) matched its season high in 18-49, and “2 Broke Girls” (1.8/6 in 18-49, 6.9 million viewers overall) hit an outright how while drawing its second largest overall audience of the season; combined, the shows beat “Scandal” by 20% in 18-49 (1.8 vs. 1.5). CBS may be seeing the advantages of an all multi-cam block, as former 8:30 p.m. timeslot occupant “Life in Pieces” never seemed to mesh as well with “Mom.” It also helped the Eye that “American Idol” is no longer in the mix, and the dark 9 p.m. dramas (“Scandal” and “The Blacklist”) are no longer formidable hits.

“Scandal” (1.5/5 in 18-49, 6.0 million viewers overall) was down 0.2 from two weeks ago to its low, and “The Blacklist” (1.3/4 in 18-49, 6.8 million viewers overall) was off a tenth from last week, but up a tenth from two weeks ago opposite the “American Idol” finale. Last night’s 0.2 deficit, though, marked the closest same-night finish to date for “Blacklist” relative to “Scandal.”

Elsewhere, ABC’s “Grey’s Anatomy” (2.0/8 in 18-49, 7.6 million viewers overall) was down a little from recent weeks but placed second in the 8 p.m. hour while NBC’s fitness competition series “Strong” (0.8/3 in 18-49, 3.0 million viewers overall) held at last week’s premiere score.

At 10 p.m., a stronger lead-in helped CBS’ “Rush Hour” (1.0/3 in 18-49, 4.6 million viewers overall), which was up a tick from the 0.9 it posted the last two weeks. It edged out ABC’s “The Catch” (0.9/3 in 18-49, 4.6 million viewers overall) and NBC’s “Game of Silence” (0.7/2 in 18-49, 3.5 million viewers overall), both of which lost a tenth from last week.

In their second week together, Fox’s “Bones” (0.8/3 in 18-49, 4.3 million viewers overall) and “American Grit” (0.7/2 in 18-49, 2.3 million viewers overall) each edged down a tenth.

And at CW, “DC’s Legends of Tomorrow” (0.7/2 in 18-49, 1.8 million viewers overall) and “The 100” (0.4/1 in 18-49, 1.1 million viewers overall) held steady.

CBS won the night in 18-49 (1.7/6), 25-54 (2.5/7), male demos and total viewers. ABC finished on top in female demos and adults 18-34 (1.0/5).