FRISCO, Texas -- The Dallas Cowboys are like a lot of teams. They know the best way to build a team is through the NFL draft.

But an issue is starting to take shape with that theory.

One player remains from the Cowboys' 2015 draft class, defensive end Randy Gregory, and he is set to be an unrestricted free agent in 2022, although right tackle La'el Collins was signed as an undrafted free agent that year and under contract through 2024. Four players remain from the Cowboys' 2016 draft: running back Ezekiel Elliott, linebacker Jaylon Smith, quarterback Dak Prescott and cornerback Anthony Brown. And two remain from the 2017 class with cornerback Jourdan Lewis signing a three-year deal at the start of free agency and wide receiver Noah Brown signing a one-year deal.

As the Cowboys prep for the 2021 draft, they also need to look at the future of their 2018 draft class.

The Cowboys have a $9.1 million decision to make on first-round pick Leighton Vander Esch and the fifth-year option. The rest -- guard Connor Williams, wide receiver Michael Gallup, defensive end Dorance Armstrong and tight end Dalton Schultz -- are entering the final years of their contracts.

It has been a good class for Dallas. Vander Esch was a Pro Bowler as a rookie and battled injuries the past two seasons. Williams has been a starter. Gallup has become a big-play threat. Armstrong has fans on the personnel side because of his versatility, and Schultz had a career-high 63 catches in 2020.

Do the Cowboys view them as building blocks or temporary fills?

If the Cowboys don't pick up the fifth-year option on Vander Esch, he would become a free agent after the season. The only other first-rounders the Cowboys have not picked up the option on have been Morris Claiborne (2012) and Taco Charlton (2017), although they signed Claiborne to a one-year deal in 2016.

The Cowboys could look to sign Vander Esch to an extension instead of just picking up the option. It could be a risky move since Vander Esch has missed 13 games in his first three seasons, but it could also be a wise move if he reverts to the Pro Bowl form as a rookie under coordinator Dan Quinn. In case you were wondering, linebacker Sean Lee missed 13 games in his first three seasons and the Cowboys signed him to a six-year extension in 2013.

Williams has started 37 of the 40 games he has been active. He has been reliable, but if he is not part of the Cowboys' future, could he be part of some kind of trade in the upcoming draft? In house, the Cowboys have 2019 third-round pick, Connor McGovern, who could slide into the left guard slot. If they draft an offensive lineman in the first round at No. 10 overall, then Rashawn Slater could be a walk-in starter.

It is difficult to separate the futures of Gallup and Amari Cooper. Cooper, 26, is entering the second year of a five-year, $100 million deal with Dallas. His 2022 base salary of $20 million is fully guaranteed on the fifth day of that league year. If the Cowboys release him, he would count $6 million against the 2022 salary cap.

It should be noted that in a year in which they needed a lot of salary-cap space, the Cowboys have yet to restructure Cooper's contract despite his youth, production and the four years remaining on his contract.

Gallup followed up his 1,107-yard, six-touchdown season in 2019 with 843 yards and five touchdowns in 2020 with four different starting quarterbacks. What could he command on the open market? Aside from Kenny Golladay ($18 million per year with the New York Giants), no other wide receiver topped $12.5 million on average in free agency this offseason. If Gallup produces again, could the Cowboys pay him $14 million to $16 million on average with CeeDee Lamb, their 2020 first-rounder, under contract through at least through 2023?

Keeping Cooper, Gallup and Lamb together at such large prices in 2022 would seem to be prohibitive.

Armstrong has 2.5 sacks in three seasons, but he can play multiple spots and fill in on special teams. Is that worth a long-term commitment, or is he part of a fungible future in which third-day picks get swapped out for other third-day picks as part of a salary squeeze?

Schultz outperformed any expectations for him after Blake Jarwin suffered a torn anterior cruciate ligament in the 2020 opener. Jarwin will be back this season, and the Cowboys believe he can be a stretch-the-field playmaker in a stretch-the-field passing game led by Prescott. Like Williams, could teams call the Cowboys during the upcoming draft regarding a trade for Schultz?

It feels like it was just a few days ago when the Cowboys selected Vander Esch in the first round of a draft that was held at AT&T Stadium. Time flies and decisions need to be made.

It is possible the Cowboys could have none, one or two players from the class of 2018 on their roster in 2022.

Building through the draft is a viable strategy, but foundations are difficult to compose.