The overtime thriller is the most-watched conference title game in five years.

A pair of overtime games in the NFL's conference championships brought huge ratings to CBS and Fox on Sunday.

CBS' primetime coverage of the AFC Championship, in which the New England Patriots beat the Kansas City Chiefs, 37-31, averaged 53.9 million viewers, making it the most-watched conference title game in five years.

That's up 27 percent from the 42.3 million who watched the 2018 NFC Championship in primetime on Fox (the two networks rotate the primetime slot each year). The last time a conference championship drew a bigger audience was in 2014, when Fox's primetime broadcast averaged 55.91 million viewers. It's the fifth most-watched championship game in either broadcast window of the past decade.

CBS drew a household rating and share of 27.5/46 for the game, also up 27 percent from the primetime window in 2018.

The earlier game on Fox, a 26-23 victory for the Los Angeles Rams over the New Orleans Saints in the NFC Championship, averaged 44.08 million viewers, even with the early-window tilt last year. The game drew a household rating and share of 24.5/48, up slightly from 24.3 a year ago. Coverage on Fox Deportes and the Fox Sports app pushed the total audience for the NFC game to 45.04 million viewers.

The two-game average of just under 49 million viewers is the highest in three years; the 2016 title games averaged 49.5 million.

Following the AFC title game, an episode of Magnum P.I. easily delivered season highs for CBS. Pending updates, the show garnered a 3.8 rating in adults 18-49 — about four times its season average — and a little above 12 million viewers, almost twice its usual audience.

Elsewhere on Sunday night, ABC's Shark Tank scored a 0.7 in the 18-49 demo, down 0.4 from the prior week's season high but in line with its season average; Supergirl and Charmed both drew a 0.3 in their returns to The CW; and NBC's Dateline posted a 0.6.

CBS lapped the field a few times with a primetime average of 13.2 in adults 18-49, pending updates. Fox was the best of the rest at 0.8, followed by ABC, 0.6; NBC, 0.5; and The CW, 0.3.

Jan. 21, 1:10 p.m. Updated viewership figures for the NFL games.