Since the team has largely stayed away from free agency, the Dallas Cowboys have relied on the NFL draft to stock their team with talent. Because of this, it's critical for the Cowboys' draft picks to make an impact commensurate with their draft slot.

With that in mind, we are going to grade the Cowboys rookie class after each quarter of the season, starting now with Weeks 1-4.

Note: Each rookie is graded on a curve commensurate with his draft slot. For example, a fifth-round pick is not graded to the same standard as a first-round pick.

Leighton Vander Esch, LB

Thanks to Sean Lee's pesky hamstrings, Leighton Vander Esch has seen a steady increase in snaps every week (22 in Week 1, 41 in Week 2, 47 in Week 3 and 58 in Week 4). Vander Esch has made the most of his opportunities, compiling 21 tackles, nine stops, on just 127 snaps, per Pro Football Focus.

Vander Esch has thrived against the run, where his football intelligence and giant tackle radius shine. Rarely fooled by misdirection, Vander Esch has consistently displayed a quick processor to read his keys and identify what the offense is trying to do. This has allowed Vander Esch to play downhill and make plays near the line of scrimmage against the run.

Really nice job of #Cowboys LB Leighton Vander Esch attacking the block properly (same foot, same shoulder) then squeezing his way by to trip up Blout pic.twitter.com/T1n8gult0k — John Owning (@JohnOwning) October 3, 2018

Vander Esch hasn't been tested a ton but he has performed admirably in coverage when necessary. He does well to get the proper depth in his drops and he's great at limiting yards after the catch. In man coverage, Vander Esch has defended running backs out of the backfield well, using his speed and large frame to minimize throwing windows to the flats.

Gets initial pulled toward the LOS by the PA, but look at the recovery by #Cowboys LB Leighton Vander Esch to retrace and blanket the cross, taking away Stafford's read.



Don't see many LBs that can move like that, especially at that size. pic.twitter.com/C2X5Czz2TA — John Owning (@JohnOwning) October 3, 2018

Overall, after having a quiet offseason and training camp, Vander Esch has exceeded expectations with the opportunities he's been given. The Cowboys defense has floundered in the past without Sean Lee, but that hasn't been the case with Vander Esch, who has arguably been the best linebacker on the field for the Cowboys in the last two games.

Grade: A-

Connor Williams, LG

Outside of his much-publicized issue with power, Connor Williams has actually been solid in his first four games as professional.

#Cowboys LG Connor Williams was much more consistent with his hand timing and placement against NYG. Showed a strong inside hand to defeat inside moves and did well to steer defenders at the POA. He continues to improve week-by-week. pic.twitter.com/R7NPOoG0Dm — John Owning (@JohnOwning) September 19, 2018

Williams has been his best when asked to pull and block in space, where he's able to show off his exceptional athleticism to stymie linebackers and defensive backs on the move. Williams' blocks have been the catalyst for a few of Ezekiel Elliott's explosive runs.

Oh look at this. Another pin-and-pull sweep and another explosive gain by #Cowboys RB Ezekiel Elliott. Beautiful blocks by Zack Martin and Connor Williams, clearing the path for Zeke to sit Earl Thomas down with a stiff arm. pic.twitter.com/YXA6rNIj9e — John Owning (@JohnOwning) September 24, 2018

In pass protection, Williams typically gets into trouble when his elbows start to flare as he's trying to anchor against a power rusher, inhibiting his ability to create the torque he needs to counter the force applied by the rusher.

This is not an every down issue for Williams, as there are plenty of snaps of him handling power without issue. The issue tends to arise when Williams cedes first contact, forcing him to absorb the force from his opponent rather than fully exerting it on his opponent. When Williams is more diligent with his hands, he tends to have more success.

Nevertheless, Williams has to be careful not to be too aggressive with his punches, as he been caught lunging, making it easy for defensive linemen to defeat his block if they are able to beat the rookie guard's hands.

Nice inside zone here to get Zeke a nice gain on first down. Connor Williams made an excellent block on the second level. Walled of the LB and showed impressive grip strength to sustain. #Cowboys pic.twitter.com/ybzvX7Yj1n — John Owning (@JohnOwning) September 17, 2018

In the run game, Williams has had some fantastic moments. Outside of his ability to block in space, Williams has proven to be effective on down blocks and when asked to climb to the second level on zone runs. What's impressive about Williams is that he has already developed a wide array of hand techniques to stymie defenders, whereas most rookies don't.

Until he's able to improve his play strength, Williams is going to go through some ups and downs. Yet, if you can see the forest for the trees, it's easy to recognize that Williams has the skill set to be a Pro Bowl caliber guard in the NFL once he rectifies his play strength issues.

Grade:C+

Michael Gallup, WR

After a dreadful start to the season, Michael Gallup finally displayed some of his promise against the Detroit Lions, hauling in a tough 37-yard reception with tight coverage on him.

Another play-action and another big gain. Phenomenal throw by #Cowboys QB Dak Prescott and a nice grab by Michael Gallup. pic.twitter.com/DXT9iAiGMy — John Owning (@JohnOwning) October 1, 2018

Thus far this season, Gallup has just five catches for 76 yards on 12 targets, running 63 routes (fifth-most of the team) and accounting for 1.21 yards per route run, seventh among the 17 rookie receivers who have run a route this season.

Gallup has fared surprisingly well as a blocker this season, showing no fear of the NFL's physicality in the run game.

Like most rookies, especially rookie third-round picks, Gallup has struggled to create separation with his routes, lacking the experience necessary to master the subtle nuances of route running. If he improves there, Gallup could have a successful career similar to Rams wide receiver Robert Woods. If he doesn't, Gallup will struggle to earn more opportunities in this Cowboys offense.

A positive performance against the Lions has Gallup moving in the right direction after struggling in the first three weeks of the season.

Grade:C-

Dorance Armstrong, DE

SEATTLE, WA - SEPTEMBER 23: Defensive End Dorance Armstrong #92 of the Dallas Cowboys tries to get passed Tackle Duane Brown #76 of the Seattle Seahawks during the second half at CenturyLink Field on September 23, 2018 in Seattle, Washington. (Photo by Otto Greule Jr/Getty Images) (Otto Greule Jr / Getty Images)

While he hasn't made a ton of splash plays, Dorance Armstrong has fared well thus far given where he was drafted.

Through the first four weeks, Armstrong has primarily been used when DeMarcus Lawrence needs a breather. He hasn't played a ton (79 total snaps in four games) and his statistics are lacking because of it - just four combined tackles this season.

From a pass rush perspective, Armstrong still needs a lot of seasoning, as he tends to rush into contact too often. Armstrong would find more success rushing the passer if he attacked the edges of opposing tackles with chops, swats and rips instead of looking to establish his long arm on nearly every rush.

Against the run, Armstrong has been stout, setting a strong edge while playing with good gap discipline. He is still lacking a bit in the play strength department, but Armstrong has the frame to add some mass in the offseason.

Altogether, Armstrong has been solid, yet unspectacular thus far in his rookie season, and it will be important for him to show some progress as the season moves along.

Grade: C+

Dalton Schultz, TE

With just three snaps to his name, Dalton Schultz has yet to provide enough of a sample size to get a real grade.

Some may make the case that if a fourth-round pick is inactive for three of the first four games of the season, that he deserves a failing grade. But before casting judgement on Schultz's ability, it's best to wait for Schultz to get more playing time.

Grade: INC

Mike White, QB

Stuck behind Cooper Rush and Dak Prescott on the depth chart, Mike White will be inactive for every game this season, barring injury.

After showing some promise toward the end of the preseason, the Cowboys are likely grooming White to be the backup quarterback of the future. Still, it's impossible to grade his regular season performance without, you know, seeing him perform.

Grade: INC

Chris Covington, LB

Much like White, Chris Covington is a promising late-round pick who is stuck at the bottom of the depth chart with little hope of rising this season. Still, the Cowboys obviously see something they like in the rookie linebacker, as the team decided to keep an extra linebacker on the 53-man roster because of him.

Grade: INC

John Owning writes about NFL player evaluation for SportsDayDFW.com. Follow him on Twitter at @JohnOwning.