Today's top sports stories:

The first day of the NCAA Tournament kicked off Thursday afternoon, with Michigan State, Butler, Wichita State (see above), St. Louis and Memphis advancing early in the day. Much more to come as the rest of the day's 16 games get under way. [CBS]

The longtime star linebacker for the Chicago Bears, Brian Urlacher, will not be clad in the orange and navy next year. Urlacher expressed surprise at the breakup, calling the Bears' offer of one year for $2 million "insulting." [Yahoo]

The Miami Heat were down 27 points to the Cleveland Cavaliers on Wednesday night, and then LeBron James led them all the way back to extend their winning streak to 24 games. Even more interesting, a fan ran onto the court in the middle of the game to urge LeBron to come back to Cleveland. [L.A. Times]

Every year during March Madness, you hear all the commentators going on about all the upsets that happen. Well, here's a look at the biggest upsets in the tournament's history. [S.I.]

Opening Day is around the corner, and that means it's time to get ready for your fantasy baseball draft. Here's a look at five potential sleeper picks and five possible breakout stars. [GuySpeed]