NEW YORK -- A regular-season NFL game drew more television viewers than the World Series.

The "Sunday Night Football" matchup between the past two Super Bowl champions was watched by 18.1 million people, compared with 15.5 million for Game 4 of the World Series.

NBC said it was the first time an NFL game earned a higher rating than the World Series, though the two have rarely aired at the same time over the years.

The World Series took an off day Monday until the schedule changed in 2007, and the NFL often didn't hold a Sunday night game during the World Series. NBC had skipped a week of "Sunday Night Football" for the first four years of its current NFL contract.

The San Francisco Giants' 4-0 victory over the Texas Rangers on Fox earned a 9.0 rating and 15 share. That's down 32 percent from the 13.3 for Game 4 of last year's Yankees-Phillies World Series and down 3 percent from the 2008 Phillies-Rays series.

The New Orleans Saints' 20-10 win over the Pittsburgh Steelers on NBC had a 10.7/17. That's down 19 percent from the 13.2 rating "Sunday Night Football" had averaged coming into the game.

Since 1991, the NFL had gone against the World Series nine times, with all but one of the football games on cable. In 1996, Game 2 of the Yankees-Braves World Series, which was pushed back a day because of rain, earned a 14.0 rating, while the Raiders-Chargers "Monday Night Football" game on ABC drew a 12.0.

The two sports will go head to head again Monday night, when the Giants try to clinch the title in Game 5 and the Houston Texans and Indianapolis Colts face off on ESPN.

Ratings represent the percentage of all homes with TVs tuned into a program. Shares represent the percentage of all homes with TVs in use at the time.