The biggest flaw on the 2014 Dallas Cowboys is their lack of a proven pass rush. In 2013, the Cowboys were ranked 25th in sacks, per NFL.com. This puts an extra strain on the linebackers and secondary in coverage. If the quarterback has more time to throw, then he has a high probability of completing a pass. That is a big reason why the Cowboys ranked 30th against the pass, per NFL.com.
An effective pass rush is the key to any great defense. Quarterbacks often get rattled by constant pressure, which makes the secondary's and linebackers' jobs easier in coverage.
Now, this season the Cowboys lost two of their most proven pass-rushers in DeMarcus Ware and Jason Hatcher, who accounted for 17 of their 34 sacks in 2013. Therefore, it would appear that the pass rush is a huge flaw for the Cowboys.
The Cowboys have tried to replace Hatcher and Ware by signing Henry Melton and drafting DeMarcus Lawrence. It is not likely that Lawrence and Melton play up to the level of Hatcher and Ware, at least this year.
So how are the Cowboys going to get any consistent pass rush?
Cowboys assistant director of player personnel Will McClay has the answer. McClay told 105.3 The Fan (via Blogging The Boys):
And for the scheme to work that we're using now – it's very evident when you go back to the Chicago Bears, Tampa Bay Buccaneers of old, Seattle Seahawks now – you've got to have depth. It's all in how you put the pieces together to build that depth of the seven-, eight-man line that you'll need in a rotation during the season if you're going to play fast and do the things that we do.
So the Cowboys will be relying on their defensive line as a whole to get constant pressure and not just a couple of players as in years past.
However, the question remains whether the Cowboys have the players on the roster right now who can pressure the quarterback on a consistent basis.
If not, the Cowboys defense will have another awful year.