​©IMAGO/Icon SportswireJust like last year, the Cowboys’ defense has once again become a talking point for the team for the wrong reasons. Set to face the San Francisco 49ers next, former Cowboys wide receiver Michael Irvin knows this one’s going to be a true test. Particularly for Dallas defensive coordinator Christian Parker.“I’m worried about that battle with Kyle [Shanahan] and Christian Parker,” Irvin claimed on The White House podcast. “And Kyle is just the best at it. So, it’s gotta be a shootout for me. Any chance that Dallas have at winning this game is got to be a shootout.”Parker, who is a defensive coordinator for the first time in his career, was hired to rebuild the league’s worst defense from last year. Over the offseason, it looked like they’d made some improvements. This defense had additions like Cobie Durant, Caleb Downs, and even veteran pass-rusher Von Miller. However, the defense has not performed as advertised.They will meet perhaps one of the best offenses in the league in the 49ers, and the offensive genius of head coach Kyle Shanahan. If Dallas, the clear underdog, can best the 7-1 San Francisco, it will be a statement for the Cowboys.The Cowboys’ coaching struggles are reaching a critical point as Dallas prepares for a massive test against San Francisco. Subscribe to stay ahead of every twist in this pivotal NFC showdown.“It will be pandemonium, because, alright, if you haven’t been consistently able to perform well, but you show yourself that you can play with the tops, or sometimes that’ll pull you towards the consistency,” Irvin opined. “You haven’t been consistently, but this will pull your towards that consistency, if you beat a team like the 49ers. And they have the talent to beat this team.”San Francisco is averaging 376.8 offensive yards per game and 29.4 points per game. The Cowboys are allowing about 26.2 points per game, putting them in 25th place in the league. The math about which is the better team is simple.Two weeks ago, during the game against the Arizona Cardinals, a team that averaged a little over 90 rushing yards per game in their previous outings, gained 202 yards on the ground against the Cowboys. It included a 63-yard touchdown run by Tyler Allgeier.“When I look at Kyle Shanahan and having these guys ready to play, the first thing I’m going to do to attack Dallas is these scheme runs,” McGinest said when Irvin asked about his thoughts. “Dallas has struggled defensively with scheme runs, and everything schemes on the back end. Who is one of the best play callers in the game. So this is Kyle Shanahan saying, ‘This young defensive coordinator has struggled with all that. I’m attacking every single issue you’ve had over the past eight weeks. I’m attacking it all.’“And this is one of the best play callers in the game of football. So you’re going to see the scheme runs, you’re going to see the motions, the shifts. You’re going to see all the d