The NFL's uniquely short season gives each game an importance that you don't find in many other sports. One game can change everything. Especially for the 2015 Cowboys.
One of the many unique things about the NFL is its extraordinarily low number of regular season games - at least compared to almost all other major sports.
The 16-game schedule makes every single game hugely important, much more so than in baseball's 162-game season, or the 82-game seasons of the NBA and the NHL. Sure, every game is mathematically important in every league, but the games in other sports simply don't carry the same weight and life-or-death quality that an NFL game does.