The first night of NCAA Tournament games on CBS suffers double-digit declines year to year.

March Madness was light on the "madness" part for CBS Thursday night, as the network's first night of NCAA Tournament games fell by double digits compared to a year ago.

The declines helped ABC's Grey's Anatomy claim the top spot in the Nielsens in primetime.

The CBS portion of NCAA coverage drew a 2.6 household rating in metered markets, down 26 percent from the first Thursday of the 2018 tournament. A blowout in the early game (Kentucky beat Abilene Christian by 35 points) and a lack of big names in the late contest (Wofford vs. Seton Hall) may have contributed to the low numbers.

Ratings for the full day, including games on TNT, TBS and TruTV, will be available later.

At ABC, Grey's Anatomy matched its week-ago 1.4 rating among adults 18-49 (tying a series low) but came out on top in the demographic. It improved some in total viewers, drawing 6.89 million people — also the best of the night. Station 19 (0.9) improved a little in the 18-49 demo and For the People held at 0.5.

NBC's Superstore (0.9), AP Bio (0.5) and Brooklyn Nine-Nine (0.6) all equaled last week's 18-49 ratings. Will & Grace (0.7) and Law & Order: SVU (0.8) each improved a little.

Gotham and The Orville both came in at 0.6 for Fox, even with their last episodes. The CW's Supernatural (0.4) and Legacies (0.3) were also steady.

CBS led the 18-49 demo in primetime with a 1.0, pending updates for its live NCAA broadcasts. ABC came in second at 0.9, followed by NBC, 0.7, and Fox, 0.6. Telemundo and Univision tied at 0.4, and The CW trailed with a 0.3.

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