A week after getting back into the NFL with the kickoff of its six-year TV package, NBC will drive forward into a big and growing-bigger portion of the sports world: fantasy football.

On Friday, NBCSports.com will launch Sunday Night Fantasy Football -- a game played online that draws as its entire universe the players who compete on NBC's Sunday Night Football during the season.

Every week, participants can visit NBCSports.com or Rotoworld.com or use their cell phone to pick players who will compete on the upcoming Sunday night game. The statistics will be compiled after every game, and winners can become eligible for prizes that include an all-expenses-paid trip to NBC's Football Night in America set in New York or a high-definition television. New games start every week based on that Sunday night's games.

We think people are looking for an easy-to-play game, NBC Sports vice president business development Kevin Monaghan said. They're going to continue to compete in their seasonlong commissioner games. ... But people are looking for a second game, an incremental game, that in a sense gives them a more engaging way to watch the game.

The fantasy game has been designed by Allstar Stats/Rotoworld.com of Somers, N.Y.

Last week, CBS SportsLine put its new spin on its lucrative fantasy sports business with what it calls Heads Up Fantasy Football. Each week, CBS SportsLine users can draft players from either the early or late games and play head to head in a three-hour window. They also can make substitutions after each quarter, giving the game an immediacy that is lacking in traditional fantasy football.

That is in addition to the seasonlong fantasy football leagues that CBS SportsLine has had for years.

At the same time, NBC also will launch the so-called Player Eliminator Game, a seasonlong game in which players are used only once, unless they appear in Sunday Night Football (when they can be used twice). It also was developed by Rotoword.com for NBC affiliates and will be offered exclusively by the NBC owned stations and their affiliates nationwide through the local stations' Web sites.

It provides you with a more engaging way to watch the game, and it's a smart marketing tool as well, Monaghan said. People who play are much more likely to watch the game and stay till the end.