The Dallas Cowboys (2-3) are coming off of a bye week and will visit the New York Giants (3-3) on Sunday in a crucial NFC East matchup. While the losses of Dez Bryant and Tony Romo have contributed to their three-game losing streak, it is the defense -- not the offense -- that has been the biggest problem for the Cowboys this season.

play 0:57 The Giants will clean things up against Cowboys The NFL Live crew says the Giants will show more consistency in Week 7 and will be able to defeat the Cowboys on Sunday.

During their three-game losing streak, the Cowboys are allowing a league-worst 6.4 yards per play. They are allowing the highest opponent completion percentage during that span and are the only defense that has not forced a turnover since Week 3.

Cowboys Defense Since Week 3 NFL Rank Yds per play 6.4 Worst Comp pct 74.0 Worst Yds per att 8.9 30th Takeaways 0 Worst

Additionally, the Cowboys are allowing points on 43 percent of opponents’ drives this season, sixth worst in the NFL, and are forcing a turnover on 5 percent of drives, second worst in the league (Jaguars, 4 percent). Both are on pace to be the Cowboys’ worst rates in the past 15 seasons.

Last season, the Cowboys went 12-4 in the regular season and led the NFL in average time of possession (32:50), mostly thanks to DeMarco Murray’s league-leading 1,845 rushing yards.

The Cowboys’ success in the running game and their ability to keep the other team’s offense off the field helped mask the Cowboys’ defensive inefficiencies. Dallas allowed the fourth-highest opponent completion percentage in the league and the sixth-highest third-down conversion rate. These defensive issues have been going on for a while.

On a per-play basis, the Cowboys' defense has been in the bottom half of the league for the past six seasons. Since 2010, only the Falcons have allowed more yards per play (5.84) than the Cowboys (5.81).

While the Cowboys might think replacing Brandon Weeden with Matt Cassel at quarterback in Week 7 is the answer, they should address their defensive issues heading into Sunday's NFC East showdown with the Giants.