The main reason for the New York Giants' stunning Super Bowl XLII upset over the previously undefeated New England Patriots isn't in the Pro Football Hall of Fame yet. Neither is Eli Manning. No defensive coordinator is more decorated than Steve Spagnuolo.

The Kansas City Chiefs are going to the Super Bowl ... again. One year after claiming their second straight Lombardi Trophy, the reigning champions punched their ticket to Super B

Without defensive coordinator Steve Spagnuolo, we might not be calling it a dynasty at all. The Chiefs leaned on their defense during their run to another Lombardi Trophy last season, and it was Spagnuolo's defense that kept the Chiefs in all of those close games they won earlier this season.

In order for the Chiefs to three-peat Spagnuolo is going to have to have another great performance against the Philadelphia Eagles, who have Saquon Barkley and the number one scoring offense in the postseason.