We expect improvement to be linear. A team with two rookie superstars has a big season, and we expect a bigger season as an encore.

The 2017 Dallas Cowboys had a problem, though. It was nearly impossible to do better than last year’s dream season.

No, the Cowboys’ 2016 season didn’t end with a championship, but it was incredible. Behind rookies Ezekiel Elliott and Dak Prescott, Dallas was 13-2 before sitting starters in Week 17. Good luck improving upon that.

The Cowboys already have more losses this season, if we eliminate that Week 17 loss last season that didn’t matter. Even though plenty of familiar faces returned, it’s not the same team.

The Cowboys were an efficient offensive machine last season with Elliott leading the way. He hasn’t been the same back this season. He had 1,631 rushing yards, 15 rushing touchdowns and averaged 5.1 yards per carry last season. He’s on pace for 1,258 rushing yards, six rushing touchdowns with a 3.7-yard average this season (and let’s not forget that it’s possible Elliott could get handed a loss in court, maybe this week, and have to sit out six games). That’s a massive drop, but it’s not all Elliott’s fault. The line isn’t the same. Doug Free was a really good, underrated right tackle. He retired this offseason. Guard Ronald Leary was good enough that the Denver Broncos gave him $9 million per year in free agency. We probably didn’t put those losses in proper context. The strength of the Cowboys was Elliott and the offensive line last season. It’s not as strong this season.

There’s a trickle-down effect. The defense was helped last season by a ball-control offense. This season the defense is getting exposed. The Cowboys were fifth in the NFL in points allowed and 14th in yards allowed last season. They’re 29th and 19th in those categories this season. They have allowed 35 points in each of their three losses. They’re allowing a 100.7 passer rating, one of seven NFL teams over the 100 mark. They’re allowing 4.6 yards per rush, tied for 25th in the NFL. Being without linebacker Sean Lee, who has missed two games due to injury, is a big blow. But there aren’t many playmakers on the defense. They seem particularly thin at cornerback (here’s a fun question: If the Cowboys could go back, are we sure they still draft Elliott over Jaguars cornerback Jalen Ramsey, the No. 3-ranked cornerback in the NFL according to Pro Football Focus?).

Let’s also add that the 2-3 Cowboys are now dealing with an explosive off-field story, with owner Jerry Jones suddenly telling everyone who will listen that he’ll get rid of any players kneeling for the national anthem. The Cowboys don’t really need that distraction right now, but Jones has put that in their laps.

It doesn’t take much to throw things off. The offensive line isn’t as good, so Elliott isn’t as productive. Dez Bryant hasn’t played like he usually does, with his numbers way down across the board. With the offense not being quite as good, the defense isn’t in a comfort zone. There’s a tougher schedule and far more expectations.

The Cowboys still have a lot of time to improve, and they’re not far off even though they’ve lost two home games in a row. Prescott is a better player after a great rookie season, even though everyone should have known he wouldn’t duplicate his 2016 numbers (like the team’s record, there was no way for Prescott to avoid regression this season). Dallas lost Sunday to the Packers on a great last-minute drive by Aaron Rodgers, and that’s excusable. There’s no reason to panic. Dallas still has enough blue-chip talent that it could rally and win the NFC East, and maybe even make a deep playoff run. It’s just not the same team as it was last season, that’s all.

Last season was special, even with the missed opportunity in the playoffs. This season can be special too. But there are a lot more obstacles in the way.

Here are the power rankings after Week 4 of the NFL season:

32. Cleveland Browns (0-5, Last week: 32)
Since there aren’t too many positives in Cleveland, what about mentioning that first-round pick David Njoku had a nice game Sunday? The tight end’s one-handed catch for a touchdown was fantastic. He should be a nice piece of their core. And clearly, Myles Garrett’s debut was a big hit.

31. San Francisco 49ers (0-5, LW: 31)
Since looking bad in Week 1, the 49ers have four losses by 11 total points, with no loss by more than a field goal. The 49ers are the second team, joining the 1994 Oilers, to lose four straight games in the same season by three or fewer points (h/t to Josh Dubow of the Associated Press). Sure, it stinks to lose all those games. But in the big picture, this is a talent-poor team that’s battling hard and coming close. They had a nice comeback to force overtime on Sunday. It could be worse.

30. New York Giants (0-5, LW: 27)
You have to wonder what’s going through Eli Manning’s mind. He’s 36, stuck on a team going nowhere this season, playing behind a bad offensive line, without Odell Beckham, Brandon Marshall and perhaps some other injured receivers too. Oh, and it certainly seems like a coaching change is possible after the season, if not during the year. It doesn’t seem like an enjoyable way to spend one of the few NFL seasons you have left.

29. Chicago Bears (1-4, LW: 26)
A fake punt? A tricky reverse/option pitch two-point conversion play? Who is this dynamic new Bears coach and what did he do with John Fox? The big story from Monday night was Mitch Trubisky, who struggled. But there are better days ahead.

28. Indianapolis Colts (2-3, LW: 30)
Let’s figure Andrew Luck comes back for the first game in November. Before then, the Colts play at a Titans team that might not have Marcus Mariota, at home against a hit-or-miss Jaguars team and at the Bengals, who we’ve seen look bad. Could the Colts win two of those games and Luck comes back to a 4-4 team? Seems possible.

27. Arizona Cardinals (2-3, LW: 20)
It was brief, like most things in the NFL, but it was fun when the Cardinals were contenders. They play an exciting style on both sides of the ball under Bruce Arians. But they’re simply not a good football team anymore and it’s hard to see a rebound coming. The offensive line isn’t good, there’s not enough offensive playmakers and the defense took on too many losses. If Arians can get them back into playoff contention, it’ll be impressive.

26. New York Jets (3-2, LW: 29)
Perhaps in December the Jets are battling for a wild-card spot and you can tell me I’m wrong. But even at 3-2, I’m still not buying this team. However, that Jaguars win looks better by the day.

25. Los Angeles Chargers (1-4, LW: 28)
Melvin Gordon had been OK but not great through four weeks. Then on Sunday he had 20 carries for 105 yards, and also six catches for 58 yards and two receiving touchdowns against a good Giants defense. Gordon hasn’t been the most efficient player in his career, but maybe he’s getting ready to heat up.

24. Miami Dolphins (2-2, LW: 25)
I wasn’t exactly on the Jay Cutler bandwagon in August, when you’d have thought from the optimism on social media that the Dolphins had just signed 1995 Brett Favre out of retirement. But I didn’t think he’d be this bad, either. Adam Gase won’t turn to Matt Moore, because try to find a coach in any sport willing to make a change that big after a win (no matter how ugly the win and no matter if the change can help the team). But it’s not like Moore would play much worse.

23. Cincinnati Bengals (2-3, LW: 24)
Changing offensive coordinators saved their season, at least for the time being. The problem is four of their next five games are on the road, and they still are digging out of a hole.

22. Tennessee Titans (2-3, LW: 19)
It’s possible this is the worst team in the NFL with Matt Cassel at quarterback. OK, maybe No. 31 ahead of the Browns. Jay Cutler tried mightily to give that game away Sunday and the Titans still couldn’t win. The Titans will be fine if Marcus Mariota returns soon, but if he misses four games? It’s over. Like the Raiders, it’s impossible to fairly rank the Titans knowing their quarterback is currently injured but will be returning soon.

21. Baltimore Ravens (3-2, LW: 23)
Alex Collins and Javorius Allen had 33 carries for 128 yards against Oakland. The Ravens have been weirdly pass-happy the past few seasons, but Sunday’s run-heavy attack is how they have to win, no matter how ugly it is.

20. Tampa Bay Buccaneers (2-2, LW: 18)
The good news is that Doug Martin looked very good in his first game this season. We know when Martin is good, he can be All-Pro good. That’ll help, because the rest of the offense was totally out of sorts last week, and really hasn’t looked great yet this season.

19. New Orleans Saints (2-2, LW: 21)
We’ll see in a hurry if the defensive improvements stick. First, Matthew Stafford and the Lions come to New Orleans, then the Saints go to Green Bay and take on Aaron Rodgers.

18. Oakland Raiders (2-3, LW: 16)
In Oakland’s last four games, Marshawn Lynch has 118 yards on 39 carries. That’s just a touch over three yards a carry, over a quarter of a season. The Lynch comeback story was awesome, but it’s also not too surprising that Lynch looks like he doesn’t have much left. Either Lynch has a sudden revival soon, or coach Jack Del Rio is going to have an uncomfortable situation as he figures out how to bench such a popular player.

17. Minnesota Vikings (3-2, LW: 17)
It’s pretty clear Sam Bradford wasn’t right on Monday night. The real question is, when will he be healthy again?

16. Buffalo Bills (3-2, LW: 15)
The Bills had three catches for 34 yards from wide receivers in a loss Sunday. Two of the catches and 25 of the yards came from Brandon Tate, who is 30 and has lasted this long because he’s a good kick returner. Jordan Matthews was injured, but the Bills need rookie Zay Jones to play better immediately and they need to seriously upgrade the position in the offseason.

15. Houston Texans (2-3, LW: 13)
The Texans lost Whitney Mercilus and J.J. Watt, perhaps their two best defensive players, for the season on Sunday night. Deshaun Watson has been fantastic, but he might have to carry this team now. The defense is going to take a step back.

14. Jacksonville Jaguars (3-2, LW: 22)
How did they look so bad against the Titans and Jets? I’m going to wait to see two good games in a row before I buy in. It’s not too much to ask.

13. Dallas Cowboys (2-3, LW: 12)
Dallas plays at the 49ers next, and it would be a good idea to win. Because here are the four games after that: at Washington, vs. Kansas City, at Atlanta, vs. Philadelphia. Wow.

12. Los Angeles Rams (3-2, LW: 9)
The Rams are fine. The Seahawks just have a great defense and weren’t going down without a heck of a fight. Jared Goff had a rough day on the whole, but it was impressive seeing him direct a nice drive at the end (and he made a nice pass to Cooper Kupp in the end zone that should have been caught). The Rams will be fine. They’re just not ready to take over the NFC West from the Seahawks yet. Considering where they were at the end of last season, that’s fine.

11. Washington Redskins (2-2, LW: 14)
If you would have asked before the season to name the most indispensable players on this team, Kirk Cousins would have been first, and Josh Norman might have been second simply because the Redskins don’t have much proven depth at cornerback. Washington has been good on defense but that could change if the cornerbacks don’t hold up while Norman is out with a rib injury.

10. Pittsburgh Steelers (3-2, LW: 2)
Ben Roethlisberger didn’t really need to say that he didn’t know if he had it anymore. We could all watch Sunday’s game and wonder for ourselves. Roethlisberger hadn’t looked great before Sunday, and then he looked awful against the Jaguars. We can try to figure out why the Steelers haven’t been great, especially on offense, but it starts with the quarterback. If Roethlisberger really has lost it – maybe he knew that was the case when he contemplated retirement this offseason – then the Steelers are not a championship contender anymore.

9. Detroit Lions (3-2, LW: 7)
The Lions defense had been quite good, but how do you let Ed Dickson torch you for 175 yards? One bad game doesn’t mean their defense is regressing to what it has been the past few years, but it is a little troubling. Also troubling is Matthew Stafford has a sprained ankle and reportedly a hamstring injury too. I’d bet on Stafford playing this week, but it’s not good news.

8. Seattle Seahawks (3-2, LW: 10)
They still have a great defense, and that was enough on Sunday. They seemed to understand the urgency of the situation against an upstart Rams team and came up with a big win. The offense is still struggling, but it’s easier to figure that out at 3-2.

7. New England Patriots (3-2, LW: 11)
You’ve probably heard the stat by now, but Tom Brady has already been sacked more times this season than he was all last season. It goes without saying that’s not good for a 40-year-old quarterback. Brady has always been great at getting rid of the ball quickly and avoiding sacks, so you have to wonder if his timing is off that way. That might be where Julian Edelman’s absence is felt most. Edelman could always get open quickly and be an easy outlet for Brady when he needed it.

6. Denver Broncos (3-1, LW: 5)
The Broncos get the woebegone Giants at home this week. It gets harder after that: The Broncos have five road games in seven weeks, and the two home games are against the Patriots and Bengals. The schedule doesn’t let up.

5. Carolina Panthers (4-1, LW: 8)
That’s two straight great games from Cam Newton. If that’s what we can expect from Newton going forward – and the last two weeks were reminiscent of his MVP season – then the Panthers can be Super Bowl contenders.

4. Philadelphia Eagles (4-1, LW: 6)
I’m very impressed with this team. The Cardinals might be a shell of what they were a couple seasons ago, but the Eagles demolished them. They’re even getting big contributions from players like Nelson Agholor, who looked like a sure bust before this season. This is the best team in the NFC East.

3. Atlanta Falcons (3-1, LW: 3)
The Falcons have to feel pretty good about catching the Dolphins at home this week. Then comes the Super Bowl rematch at New England.

2. Green Bay Packers (4-1, LW: 4)
The Chiefs deserve the No. 1 spot, but this is the team that seems to have the highest ceiling in the NFL. Consider that the Packers have dealt with pretty significant injuries and are 4-1. At some point they’re going to get healthy, and they’ll still have Aaron Rodgers when they do.

1. Kansas City Chiefs (5-0, LW: 1)
If the Chiefs beat the Steelers at home this week, they’ll be 6-0 with wins (and the tiebreaker) against the Patriots, Texans and Steelers. If that happens, they couldn’t possibly have a clearer path to the No. 1 seed in the AFC.

– – – – – – –

Frank Schwab is the editor of Shutdown Corner on Yahoo Sports. Have a tip? Email him at shutdown.corner@yahoo.com or follow him on Twitter!
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