By Chad Finn, Globe Staff

It didn't take long for Tom Brady and the Patriots to take the drama out of their divisional playoff game versus the Denver Broncos last night, building a 28-point halftime lead en route to a 45-10 victory.

And because the outcome was all but decided before the prime-time matchup was halfway to completion, the ratings for the broadcast on CBS ended up being merely very good rather than the massive numbers that some anticipated because of the appealing matchup of Broncos phenomenon Tim Tebow against Brady and the three-time champion Patriots.

According to CBS this afternoon, it's broadcast scored an average overnight household rating/share of 20.6/34, making it the highest-rated prime time playoff game in 11 years. The rating/share peaked at a 24.1/39 from the 9-9:30 p.m. window, which is right about the time the Patriots put it out of reach.

The key phrase here is "prime time.'' The 4:30 p.m. window on Sunday is the most appealing ratings-wise, and chances are that today's Giants-Packers game on Fox will put up bigger numbers than the Patriots-Broncos did on Saturday night, particularly if the game is competitive. The most-watched divisional game in NFL history is the Jets' 28-21 victory over the Patriots on January 16, 2011. That game, which kicked off at 4:30 p.m. on a Sunday, earned a 26.2 overnight rating, a 44 share, and had 43.5 million viewers on CBS.

The Patriots-Broncos game wasn't even the highest-rated game Saturday. The 49ers-Saints instant classic, which aired at 4:30 p.m. on Fox, grabbed a 21.7 rating.

I'll update here with the ratings from the Boston market when they become available.

Ratings are the percentage of all homes with televisions tuned into a program, while share is the percentage of homes that have televisions in use at the time. Overnight ratings are a measure of the 56 metered markets in the country.