Rotowire has teamed up with Yahoo! Sports this Fantasy Football season to give our users the opportunity to play against the fantasy pros.

Each week we'll offer Rotowire users a chance to sign-up for a 12-team fantasy football league that pits them against one of our fantasy football experts.

The season-long NFL commish leagues will be hosted on Yahoo! Sports, which is the leading fantasy provider on the Internet, home to over 5 million fans playing the #1 fantasy football game available - all for free!

This week our users will be pitted against Rotowire fantasy guru and SiriusXM co-host Derek VanRiper. The league will be filled first-come, first-served. To receive an invite to the league, please email me at shannon@rotowire.com.

If you don't get into this week's league, we'll have future challenges with a new expert each week until the football season kicks.

Also, be sure to check out why Yahoo! Sports is the #1 FREE Fantasy Football game on the web. Offering:

- Same day drafts
- Custom playoff seeding
- Game-time waivers
- Player availability across all leagues
- New Yahoo! Fantasy Football mobile app for 2013 season with better stabilization & increased features
- Pro Leagues - step it up a notch and play in public cash prize leagues

Get ready for kickoff by signing up now!