A history of trouble for big favorites in conference title games

Both New England Patriots and Seattle Seahawks are favored by at least a touchdown this weekend in the conference title games, which would seem to indicate they are headed for a Super Bowl matchup.

The Seahawks are a 7.5-point favorite over the Green Bay Packers in the NFC Championship Game and the Patriots are 7-point favorites over the Indianapolis Colts in the AFC Championship.

But this info may surprise you. Each of the last four times that both conference title games featured touchdown or more favorites, dating back to 1998, one of the favorites lost outright, according to Pro-Football-Reference.com.

Here are the four upset winners in those championship games:

The 1998 season (Jan. 17, 1999 NFC game) -- Atlanta was an 11-point underdog at Minnesota, but the Falcons won 30-27.

The 1999 season (Jan. 23, 2000 AFC game) -- Despite handing Jacksonville both its regular-season losses that season, Tennessee entered the game a 7-point underdog, but defeated the Jaguars 33-14.

The 2001 season (Jan. 27, 2002 AFC game) -- New England was a 10-point underdog to Pittsburgh, but the Patriots won 24-17.

The 2007 season (Jan. 20, 2008 NFC game) -- The Packers were 7.5-point favorites over the New York Giants, who won the game 23-20.

Will that trend continue on Sunday?