You only get one chance to make a good first impression, and the Dallas Cowboys certainly didn't do that in their first regular season action of the 2018 season. The eternal optimism that permeated the Cowboys faithful prior to kickoff was quickly replaced by the venomous pessimism of a loss after the Panthers' 16-8 victory.

While the Cowboys defense was able to put up a valiant effort, the offense failed to get much going throughout the game. Ezekiel Elliott was largely ineffective, Dak Prescott struggled with his accuracy down the field and the offensive line was overmatched by the Carolina front seven all game long.

Even though this game wasn't pretty from a Cowboys perspective, it is important to not make any definitive conclusions based on Sunday's action. It is just the first contest in a 16-game season and doesn't necessarily fall in line with what will happen the rest of the season. In fact, the Cowboys have made the playoffs the last two times they started 0-1, so don't give up on the season yet.

With that said, let's take a look at a few things we learned from the Cowboys' loss.

Cowboys O-line continues to strugglewhen not at full strength

Last year, the Cowboys struggled mightily on offense without one of their All-Pros on the offensive line -- Sunday was more of the same.

Joe Looney wasn't the problem, but the offense certainly missed Travis Frederick at the center position. Frederick does so much for the offense that it's hard to quantify what losing him truly means.

To the Panthers' credit, they took full advantage of the Cowboys' inexperience up front. Carolina did a great job of scheming one-on-one opportunities for Kawann Short against rookie guard Connor Williams, and Short took full advantage. Here's an example:

Kawann Short with the mean arm-over vs Connor Williams pic.twitter.com/puCZjxaFhN — Ty Wurth (@WurthDraft) September 9, 2018

On this play, Carolina aligns Short on the outside edge of Williams with a defensive end aligned wide against Tyron Smith, making it nearly impossible for the Cowboys to give Williams help. Short takes full advantage of the rookie, snatching the outside edge of Williams before employing a smooth arm-over move to beat the block, apply pressure and sack Prescott.

Notice how Looney immediately looks to his left after the ball is snapped -- he's looking to help Williams. However, since Short chose to stay on Williams' outside edge, Looney is forced to double team Carolina's nose tackle with Zack Martin.

Williams wasn't the only offensive lineman who struggled, however, as Smith and La'el Collins both had their share of issues throughout the game. Smith was mostly solid, but two costly penalties ruined a couple of Dallas' early drives. Collins was flagged a couple times as well, but he also had trouble blocking Julius Peppers throughout the game, giving up a key pressure as Prescott looked to find Deonte Thompson for a fourth-down conversion late in the fourth quarter.

Altogether, the Cowboys' offensive line gave up six sacks and a boatload of pressures to the Panthers, who didn't allow Prescott to get comfortable all game. This is especially disheartening against a defense that came into the season with the 22nd-best pass rush in the NFL, per Pro Football Focus.

In the run game, the unit as a whole struggled, as Dallas accounted for just 94 rushing yards on 22 carries. The offensive line was unable to displace defenders and generate movement in the running game. Furthermore, the unit struggled as a whole getting to the second level, as linebackers Luke Kuechly and Shaq Thompson accounted for 22 total tackles.

Overall, it was an uninspiring effort from the Cowboys' offensive line, and the effects were felt throughout the offense. Prescott was unable to get into a rhythm passing because his internal clock was sped due to the number of Carolina defenders in his face all game. The receivers were unable to generate enough separation throughout the game, but when they did, Prescott couldn't take advantage because of the pressure in his face. And Elliott was unable to find any open creases until the fourth quarter, forcing the Cowboys' run-first offense to sputter in the first three quarters.

Dallas' foundation is its offensive line, and if it continues to show cracks, the entire house is going to fall down on the offense.

Lack of discipline killed Cowboys' chances

It's never a good sign when a team has more penalties (10) than points (eight) in a game, as was the case Sunday when Cowboys looked rusty and undisciplined for large stretches against the Panthers.

The offense was hampered by costly penalties while miscommunication and sloppy tackling gave Carolina all the offense it needed. The Dallas defense was especially poor against the zone, as illustrated here:

Here, the Panthers are running a zone read from a shotgun set using 11 personnel (one running back, one tight end, three wide receivers). While running back Christian McCaffrey and the offensive line run an inside zone concept, Newton reads the back-side edge defender, DeMarcus Lawrence, at the mesh point. With Lawrence crashing down, it leaves Newton enough space to waltz in for the Panthers' first touchdown of the game.

If Lawrence stays home and keeps the back side contained, Newton would simply hand the ball to McCaffrey. However, if Lawrence crashes down to stop McCaffrey (as he does in the play above), Newton will keep the ball and run to the vacated area. Thus, Newton has the option to hand the ball off or run the ball himself based on the "read" he makes on the back-side edge defender.

Typically, if a defense has its defensive end crash down on the run, one of the second-level defenders will "scrape" over to the area vacated by the defensive end to defend the quarterback on the zone read. The Cowboys failed to do so throughout the first half, as Dallas' second-level defenders bit hard on the inside zone action, leaving Newton open to gouge the defense for 58 yards and a touchdown.

Dallas made an adjustment later in the game, opting to use safety Jeff Heath as the scraping second-level defender:

On this play, Taco Charlton crashes down on the run while Heath "scrapes" over to defend Newton on the zone read, resulting in a miniscule 1-yard gain.

The adjustment worked, but it may have been too little too late for a defense that had to play lights out to give the Cowboys a chance.

Lawrence picks up right where he left off

Enough of the negative stuff. Even though they suffered a disappointing loss, there were a few bright spots for the Cowboys, particularly Lawrence.

He picked up right where he left off last season, finishing with seven tackles, three for loss, a sack and a fumble recovery. Whether it was a run or pass, the Panthers had no answer for Lawrence coming off the edge, as the Boise State product showed off his blue-chip talent throughout the game.

Lawrence did an excellent job of varying his pass rushes throughout the game, making it hard for Carolina's right tackles to get in a rhythm in pass protection. Lawrence consistently softened the edge with swats, clubs and cross-chops to defeat the tackle's hands while trimming a tight path to the pocket with proper footwork. Here's a great example:

Here, Lawrence is lined up on the outside edge of Daryl Williams, who was a second-team All-Pro last season. After the ball is snapped, Lawrence explodes out of his stance directly toward Williams, causing Williams to take a tight pass set in an effort to defend the inside move. Once Lawrence identifies Williams' set, he employs a stutter step, forcing the Carolina right tackle to move ever so slightly inside. From there, Lawrence sticks his inside foot in the ground and explodes to the outside, using a well-timed cross-chop move to beat Williams' two-hand punch. Despite losing his footing, Lawrence does a phenomenal job of getting his hips and toes pointed toward Newton, allowing him to generate pressure and affect the throw.

Even though Lawrence was called for a roughing the passer penalty -- which was bogus because he was forced to go low on Newton as a result of the guard's cut block -- it's still a great demonstration of his effectiveness as a pass rusher.

Against the run, Lawrence was just as productive, using his quickness to penetrate gaps and his strength to set a strong edge. Lawrence is one of the few edge defenders in the NFL who can similarly affect the game as a pass rusher and run defender.

While the rest of the team looked as if it was knocking off the rust, Lawrence was already in mid-season form. Hopefully the rest of the Cowboys' roster catches up before it's too late.

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