The Dallas Cowboys’ offense must change this off-season.

We all know it.

Jason Garrett’s offensive scheme, which is essentially the same scheme the Cowboys used to win championships in the ‘90s, is a relic.

It’s a system based on personnel - not scheme, which works just fine when you have the proper personnel at your disposal- and when it doesn’t the Cowboys struggle to move the ball.

When an offensive system is based on scheme - not personnel- then it can absorb key personnel losses a lot better.

All you have to do is look at the teams in the Super Bowl to prove it.

Name all the star offensive skill position players Tom Brady has had, while leading New England to eight Super Bowls.

Look at how Philadelphia won a championship after trading for its starting running back in October, losing its star left tackle midway through the season and quarterback Carson Wentz, who was in the midst of a MVP season, in December.

When an offensive system is built on scheme it’s a lot easier to find plug-and -play players.

When the NFL suspended Ezekiel Elliott, the Cowboys were in the midst of a five-game stretch where they were averaing 32.4 points and 406.2 yards a game.

But when Elliott went out, they scored fewer than 10 points in three consecutive games for the first time in franchise history.

When left tackle Tyron Smith missed a game against Atlanta, the Falcons sacked Dak Prescott eight times.

Prescott has an idea of how he wants the Cowboys’ offense to look next season.

“I think it just means if you watch a little bit of maybe what the Panthers are doing or what the Chiefs did, just the RPOs, the run-pass options, just allowing me to use my feet if necessary more," Prescott told USA Today in Minneapolis. "Allow me to go out there and be more comfortable in everything I'm doing."

In five years with Kansas City, Alex Smith averaged 66 carries and 350 yards per season. Cam Newton has averaged 118 carries and 617 yards a season for Carolina.

He’s had four seasons with more than 120 carries, including two seasons with more than 130 carries.

No way, the Cowboys want Prescott running that much. He’s averaged 57 carries and 320 yards in his first two seasons.

The problem, of course, with running that much is that it puts your quarterback in jeopardy.

Run-pass options are good plays, but you can wind up taking the ball out of your best players’ hands.

That happened last December against Seattle, which is why the Cowboys had three plays inside the Seattle 5 and Elliott never touched it.

“The Chiefs do a great job of utilizing their running back’s and quarterback's feet,” Prescott told USA Today, “not always running with them, but scaring the defense with it.”

The key is to make the offense difficult to stop by giving it a variety of options.

Garrett is fond of saying the Cowboys like to attack a lot of different ways with a lot of different players. He’ll tell you the Cowboys like to attack horizontally and vertically.

But it’s also based on Prescott finding the best matchup and that player winning his matchup. When he doesn’t, the offense bogs down, the big plays disappear and the Cowboys struggle to score.

We all saw that happen too many times in the second half of the season, which is Prescott averaged 188 yards passing per game with six touchdowns, nine interceptions and a 74.0 passer rating.

In his first 24 games, he averaged 229 yards passing per game with 38 touchdowns, nine interceptions and a 102.4 passer rating.

The goal should be to create more options within the offense, so it creates some easier throws for Prescott. Every pass shouldn’t have to be a contested catch. A scheme with some pick plays and rub routes and bunch concepts can give Prescott a few easy throws every game.

That might just be enough too fix the Cowboys’ broken passing game and earn Garrett another season.