The NFL's epic playoff game between the Buffalo Bills and Kansas City Chiefs was the most-watched event on television since the last Super Bowl.
Nielsen said it reached nearly 43 million television viewers on Sunday night.
During the fourth quarter in Kansas City, the game's audience share was 90 — meaning 90% of the television sets on at the time were tuned in to the game.
All four games ended with a score breaking up a tie game, so the television audiences swelled instead of falling off.
As the Bills-Chiefs game went into overtime, for instance, the Nielsen company said an estimated 51.7 million people were watching.
The entire weekend was full of great football, with all four NFL Divisional Playoff games coming down to the wire.
According to NFL Research, for the first time in playoff history, Saturday and Sunday's games were decided by a combined total of 15 points, where fans watched the Bengals, 49ers, and Rams win on game-winning field goals.
The conference championship games take place on Jan. 30 as the Bengals take on the Chiefs and the Rams host the 49ers.