NCAACBS Sports and Turner Sports’ exclusive coverage of the 2014 NCAA Men’s Basketball Tournament across TBS, CBS, TNT and truTV scored the highest rating for the opening Thursday since the tourney expanded to four telecast windows for the entire day in 1991. Yesterday’s games averaged a 6.0/14 overnight rating/share, up 3% from a 5.8/14 in 2013, according to Nielsen metered-market ratings. The overall tournament average rating, including the NCAA First Four play-in games, stands at 5.6/12 — up 8% from 5.2/12 last year – which is also the highest rating at this point in the tourney since ’91. Thursday’s coverage, which made NCAA Tournament history with four overtime games in a day — not to mention some big-time upsets — boasted ratings growth across its telecast windows. The total-day numbers are some solace to CBS, whose primetime tourney ratings were down 31% last night compared with 2013 in non-time-zone-adjusted fast nationals.

The first daytime telecast window (noon-4:45 PM ET) averaged a 4.6/15 to deliver the highest rating for the time slot in 23 years. The second daytime telecast window (2:45-7:15 PM ET) averaged a 5.4/14 to garner the second-highest rating for the slot since ’91. The first primetime telecast window (6:45-10:30 PM ET) averaged a 7.7/15  — also best in time slot in 23 years. The second primetime window (9:30 PM-1:45 AM, ET) averaged a 6.2/12.