The NCAA Tournament is off to its strongest start since CBS and Turner networks began broadcasting all games in 2011. The event averaged 9.8 million viewers across its first three days, a 5% increase over last year, according to Nielsen.

Thursday's opening-round games across CBS, TBS, TNT and truTV matched that figure at 9.8 million, up 6% from the prior year. The primetime window, which included VCU's 82-78 upset of North Carolina, averaged 12.5 million, making it the most-watched first-round window in tournament history.

The First Four on Tuesday and Wednesday drew a combined 7.5 million viewers on truTV. Miami (Ohio)'s 89-79 victory over SMU on Wednesday averaged 2.8 million, the most-watched First Four game ever held in Dayton, Ohio.