FRISCO, Texas -- When Bill Parcells took over as Dallas Cowboys coach in 2003, he was struck by the size of his new team's linebackers.

For years, Parcells' linebackers were giants even when they were New York Giants. Big, strong and athletic. Think Lawrence Taylor, Carl Banks and Harry Carson. When he came to the Cowboys, the linebackers, highlighted by Dat Nguyen and Dexter Coakley, were anything but big.

"If this were the circus, we could fit them all into one of those Volkswagens that 10 clowns climb out of," Parcells once joked.

As the Cowboys look to remake their defense in 2020, Parcells' analogy is called to mind because of the difference in body type coach Mike McCarthy and coordinator Mike Nolan want in their defensive line.

It's not as if the Cowboys' defensive tackles from a year ago -- Antwaun Woods, Maliek Collins, Christian Covington and Trysten Hill -- could fit in one of those Volkswagens, but they were not exactly considered big. Former defensive coordinator Rod Marinelli wanted a defense built on speed and quickness. Size was not a prerequisite.

Woods, Hill and Collins, who has joined the Las Vegas Raiders, were listed at 310 pounds. Covington, who is unsigned, was listed at 300 pounds. Hill is the tallest at 6-foot-3. Collins and Covington are 6-2. Woods is 6-1.

In the first two weeks of NFL free agency, the Cowboys agreed to deals with Gerald McCoy and Dontari Poe. McCoy is 6-4, 300 pounds. Poe is 6-3, 346 pounds.

They come to the Cowboys from the Carolina Panthers, who ran a 3-4 defensive scheme. Nolan has a deep background in the 3-4, including a one-year stint with the New York Jets when Parcells was their general manager.

But that doesn't mean the Cowboys are moving to a 3-4. What it does mean is there could be some 3-4 principles that come into play with defensive tackles occupying two gaps instead of one to help the linebackers make more plays.

It also opens up the possibilities of not being too strict on traits for specific positions, which is one reason the Cowboys chose Taco Charlton over T.J. Watt in the first round of the 2017 NFL draft. While they knew Watt could rush the passer, they did not believe he could be an every-day defensive end. In this era of specialization, teams have to be willing to adapt.

"Really part of it is developing," McCarthy said at the scouting combine. "In Green Bay, when you're picking 26, 27, 28 [in each round], you're down there in the 20s every year, when you're throwing away good players because they don't fit your system, you got to take a hard look at your system. If the guy is a good football player, he can play for me. That's something I've always played. Now, you want your team to look a certain way. I still believe in body types and measurables, and you have limits. But if the guy is a really good player ..."

McCoy has been one of the more dominant defensive tackles of his era with 59.5 sacks since 2010. He had only five last season with Carolina, but the Panthers had a diverse pass rush that allowed them to finish second in the league with 53 sacks. The Cowboys had 39. The last time they had close to 53 sacks in a season was 2008, when DeMarcus Ware was entering his prime.

The biggest issue some had about the Cowboys' lack of size up front had to do with their work against the run, yet under Marinelli the Cowboys had a top-10 run defense in four of his six seasons as coordinator and were ranked 11th in 2019.

The Cowboys gave up nine runs of at least 20 yards in 2019, up from six in 2018. They gave up 46 runs of at least 10 yards, up from 39 in 2018.

The bigger the players up front, the harder it should be for the opponents to create creases for the runner. At least that's the premise under which the Cowboys are now operating.

The additions of McCoy and Poe are just the start of the changes.