Jerry Jones made a sound decision to hire Mike McCarthy. However, the fate of the Dallas Cowboys does not rest with the man who coached Aaron Rodgers for years in Green Bay. Rather, the Cowboys’ Super Bowl chances depend on what Jim Tomsula can do with a potentially dominant defensive line. And based on his track record, the 52-year-old coach could be the savior Dallas fans have desperately waited for.

Mike McCarthy made a critical hire in Jim Tomsula

NFL head coaches garner most of the credit, but they depend on position coaches to help players develop. In hiring Jim Tomsula as his defensive line coach, Mike McCarthy scored a critical asset. The Pennsylvania native has been coaching since 1989. Tomsula actually spent several years in NFL Europe before landing with the San Francisco 49ers.

From 2007-2014, he served as the team’s defensive line coach. Under his watch, San Francisco boasted one of the most dominant units in the league. In fact, new Cowboy Aldon Smith enjoyed the most productive stretch of his career under Tomsula’s watch.

Smith racked up 42 sacks and earned first-team All-Pro honors within his first three years in the league. Tomsula’s tough-nosed coaching and demand for excellence brought the best out of the talented pass-rusher.

Following a one-year stint as the 49ers’ head coach, Tomsula took his talents to Washington, where he helped Jonathan Allen and Da’Ron Payne harness their natural athletic gifts. A day after McCarthy officially became the ninth head coach in Cowboys’ history, Tomsula became the team’s defensive line coach.

Tomsula will be tasked with maximizing a talented defensive line

Even a veteran coach like Jim Tomsula must have trouble containing his excitement about the possibilities in Dallas. Having coached a number of elite players in the past, Mike McCarthy’s critical assistant will benefit from working with a number of established stars.

DeMarcus Lawrence headlines a group that boasts dominant potential. The 6-foot-3, 265-pound defensive end has racked up 39 sacks in his career, including a career-high 14.5 in 2017. Lawrence could post even better production thanks to some key offseason additions.

Though the Cowboys suffered a brutal blow with Gerald McCoy’s season-ending injury, they still have plenty of intriguing pass-rushers. Everson Griffen arrives with a rock-solid track record of production. The former Minnesota Vikings standout has earned four Pro Bowl berths and racked up 74.5 sacks in 10 seasons.

Dontari Poe brings size and rare athletic ability to the defensive tackle group. His importance only increased in the wake of McCoy’s injury.

Plus, the Aldon Smith comeback storyline should be fun to follow. He has turned heads in training camp and nobody knows his personality and skill set better than his former defensive line coach.

Why McCarthy’s assistant controls the fate of the Cowboys

The Cowboys should have no trouble moving the ball and putting up points in 2020. Dak Prescott, Ezekiel Elliott, and Amari Cooper anchor a unit that added another big-time playmaker in CeeDee Lamb. Add in Michael Gallup and you have three wideouts who could easily eclipse 1,000 receiving yards this season. Overall, Dallas has all the pieces on that side of the ball to field a top-five offense.

However, the Cowboys desperately need their defensive line to play up to its potential in order to make a deep playoff run. Sure, Dallas has two young star linebackers in Leighton Vander Esch and Jaylon Smith. However, that duo stands no chance of succeeding without strong play up front.

Plus, Dallas lost top cornerback Byron Jones in free agency. On paper, the Cowboys’ secondary does not feature a bonafide No. 1 corner.

However, a ferocious pass rush and strong play up front can mask any talent deficiencies that exist on the back end. If Jim Tomsula’s group plays up to its potential, Dallas could easily have multiple players with double-digit sacks. However, if the Cowboys can’t stop the run and get after the quarterback, their secondary will get exposed.

That could lead to serious trouble in Dallas even with a potentially high-flying offense. Ultimately, Jim Tomsula controls the fate of the Cowboys this season. If his defensive line dominates, Dallas can make a Super Bowl run. If not, Jerry Jones will see another season end in bitter defeat.

All statistics courtesy of Pro Football Reference.