Through two seasons as San Francisco 49ers head coach, Kyle Shanahan was 10-22. He had legitimate excuses. But the NFL is an impatient, results-based league.

The outcomes have changed. Maybe there was skepticism about the 49ers’ 3-0 start due to the level of competition. There shouldn’t be many questions anymore after the 49ers improved to 4-0 with a 31-3 beatdown of the Cleveland Browns. The Browns have their issues, but they still have a lot of talent. The 49ers absolutely crushed them.

We’re searching for the best team in the NFC, with everyone showing flaws. Why not the last undefeated team in the NFC?

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The 49ers’ moves the past few years didn’t always follow conventional wisdom, but they have come together very well. The 49ers have a lot to like a quarter of the way into their season.

San Francisco runs the ball as well as anyone in the NFL. It rushed for 259 yards against Cincinnati. It rushed for 275 yards against Cleveland on Monday night. The 49ers have a seemingly endless assembly line of running backs and they all contribute. Fullback Kyle Juszczyk suffered an apparent knee injury Monday, and that could affect the 49ers’ run game going forward. But Shanahan has always orchestrated good run games and should adjust.

You can win games in the NFL by running it well and playing defense, and the 49ers’ defense might be a lot better than we expected. Monday night was a revelation. Baker Mayfield was awful, completing just 8 of 22 passes for 100 yards. He had a 13.4 passer rating. The 49ers had a lot to do with it. They swarmed Mayfield all game. Nick Bosa, the No. 2 pick of the draft, was unblockable. He had two sacks and impacted several plays.

“We’re a championship-level defense and we’re going to get after you all game,” Bosa told ESPN’s Lisa Salters after the win over the Browns.

The last remaining element for the 49ers could be the passing game. Jimmy Garoppolo, coming off a season-ending ACL injury last year, hasn’t been bad. He just hasn’t been great. Before Week 5, Garoppolo was 16th among quarterbacks in Pro Football Focus’ grades. That fits. He has been an average quarterback. He’s averaging 230 yards per game. He has seven touchdowns and four interceptions in four games. There’s nothing wrong with Garoppolo to this point. But for the 49ers to unlock a true championship ceiling, they’ll need more from Garoppolo. They’ll need him to play like a $137.5 million quarterback. Garoppolo being able to take the passing game to another level might be the last remaining piece of the puzzle.

That’s a concern for another day. Niners fans should be excited after a few lean years. It’s the first time the 49ers are 4-0 since 1990. They’re one of two undefeated teams left, along with the Patriots. They couldn’t have looked any better on Monday night against the Browns. They’re going to be a factor all season.

Here are the Power Rankings after Week 5 of the NFL season:

32. Miami Dolphins (0-4, Last week: 32)

Here’s the truth: Nobody wants to lose all 16 games and this Redskins game is one of the few on the schedule in which the Dolphins don’t appear overmatched, but it’s much better for Miami to lose. It doesn’t do much good to tank if you’re going to beat a team that could steal the No. 1 overall pick from you.

31. Washington Redskins (0-5, LW: 31)

Here are some of the coaches that have failed to finish their time with Daniel Snyder’s Redskins with a winning record: Marty Schottenheimer (seventh in NFL history with 200 career wins), Mike Shanahan (two Super Bowl titles), Joe Gibbs (Hall of Fame), Steve Spurrier (one of the best college coaches ever), Norv Turner (one of the NFL’s better offensive coordinators for more than two decades). I get why Jay Gruden had to go, but we all know he’s not the problem. If those coaches couldn’t win with the Redskins, who can?

30. New York Jets (0-4, LW: 30)

If Adam Gase had any track record of real success without Peyton Manning, I’d give him more of a pass for this offensive debacle with the Jets. Not many coaches are going to turn Luke Falk into a productive passer. But Gase hasn’t really shown much outside of when he coached Manning, and that was years ago. And Manning might have had just a little more to do with that success than Gase.

29. Cincinnati Bengals (0-5, LW: 29)

Watching the Bengals’ offense do absolutely nothing for three quarters against a bad Cardinals defense gives me no hope this is going to get better anytime soon.

28. Arizona Cardinals (1-3-1, LW: 28)

Three of the four winless teams are headed by coaches in their first year on the job. At least Kliff Kingsbury doesn’t have to worry anymore about when his first win will come. That has to be a horrendous feeling.

27. Atlanta Falcons (1-4, LW: 26)

Now that the Redskins have broken the seal on head coach firings for the 2019 season, you have to assume Falcons coach Dan Quinn is in win-now mode, starting immediately. The Falcons have shown almost nothing this season, especially on defense. Quinn fired all of his coordinators after last season and took over defensive play-calling.

26. Pittsburgh Steelers (1-4, LW: 25)

Mike Tomlin deferred after winning the coin toss in overtime. I suppose there’s some argument to be made for it, but I’m not sure I buy his argument for it. “Man, did you see our kickoff return in this football game? Did you see their kickoff team?” Tomlin said. “Every time they put the ball on about the 2-yard line and [Justin] Tucker hung the ball at about 4.5 seconds, we couldn't get back to the 15. Why would I sign up for that?” The Ravens punted on their first overtime possession, but just because the result was positive doesn’t mean the decision was right.

25. Denver Broncos (1-4, LW: 27)

It took Vic Fangio a really long time to get his first win as an NFL head coach. It came a month and a couple weeks after his 61st birthday. One positive for the Broncos this season is a big leap for second-year receiver Courtland Sutton. Sutton’s long touchdown early in Sunday’s win over the Chargers set the tone. He’s going to be a good one.

24. New York Giants (2-3, LW: 24)

Lost in the Daniel Jones excitement was the issue with the Giants’ pass defense. The Vikings went from a near revolt over the lack of a passing game to Kirk Cousins shredding the Giants for 278 yards in the first half of an easy win. Everyone is going to be able to move the ball up and down the field on them.

23. Tennessee Titans (2-3, LW: 22)

I remember when Lane Kiffin sent out Sebastian Janikowski for a 76-yard field-goal attempt. I had more confidence in that one going in than Cairo Santos hitting a 53-yarder in the fourth quarter on Sunday. And that field goal really meant very little to the Titans’ chances of winning. We see bad decisions by coaches each week in situations that call for them to go for it on fourth down, but Mike Vrabel’s decision to try a long field goal with a struggling kicker on fourth-and-4, trailing 14-7 to the Bills, will end up being the worst of the 2019 season.

22. Cleveland Browns (2-3, LW: 12)

That was one disheartening performance. The Browns have played five games and didn’t play well in four of them (if you watched the Jets game, you know it wasn’t an impressive win). The most troubling part might be Baker Mayfield’s extreme regression from a fantastic rookie season. It’s hard to believe Mayfield isn’t good after what we saw from him last season. But he clearly doesn’t look like the same player.

21. Jacksonville Jaguars (2-3, LW: 21)

D.J. Chark was a raw athlete who didn’t do much last year as a rookie. In Year 2, he has been phenomenal. It was a boom-or-bust type of pick, and the Jaguars nailed it. He might already be one of the NFL’s best receivers.

20. Tampa Bay Buccaneers (2-3, LW: 20)

It’s hard to believe Mike Evans got shut out in a game. Saints cornerback Marshon Lattimore played a great game, but it’s still shocking. Especially because O.J. Howard continued his disappearing act. The Bucs are confounding in many ways.

19. Los Angeles Chargers (2-3, LW: 15)

I’m not sure there’s another franchise in all of sports more endlessly frustrating than the Chargers. The Chargers had a moment of hope they could come back and beat an 0-4 Broncos team when they got an interception deep in Denver territory on Sunday. Then Philip Rivers immediately threw an interception into the end zone. That’s the Chargers, in one sequence.

18. Detroit Lions (2-1-1, LW: 18)

Next two Lions games: next Monday night at the Packers, then home vs. the Vikings. If the Lions are going to be a factor in the NFC North this season, that seven-day stretch is the key.

17. Baltimore Ravens (3-2, LW: 16)

I’m losing faith in the Ravens. Had Mason Rudolph stayed in the game, it seemed the Steelers would win. The Steelers still almost won with Devlin Hodges, who most NFL fans had never heard of before about 2 p.m. Eastern time on Sunday. Baltimore’s resumé of wins (Dolphins, Cardinals, Steelers down to their third-string quarterback) doesn’t look too good.

16. Houston Texans (3-2, LW: 17)

Since nobody but quarterbacks win MVPs anymore (more on this in the Panthers section), keep an eye on Deshaun Watson. Patrick Mahomes’ last two weeks has dropped him back to the pack. Watson had a bad game in Week 4 but bounced back with a perfect game (158.3 rating) on Sunday. He has 11 touchdowns and one interception. It wouldn’t surprise me at all if he ends up as the popular MVP pick at midseason and goes on to win it.

15. Oakland Raiders (3-2, LW: 23)

Come down a rabbit hole with me … could Jon Gruden win NFL Coach of the Year? Oakland has gone from 4-12 last year to three wins before mid-October this year, and that happened after the Raiders traded for a Hall of Fame talent at receiver and he never played a down for them. On Sunday, Oakland moved the ball well against a phenomenal Bears defense and didn’t even have No. 1 receiver Tyrell Williams. I’m not sure if Gruden can get enough wins to get the Raiders a wild-card spot, but if he does …

14. Indianapolis Colts (3-2, LW: 19)

Sunday night’s Colts win might end up as the most impressive victory a team gets this season. Not many teams will win at Kansas City (or New England) this season. Colts defensive coordinator Matt Eberflus is becoming an interesting figure. NFL teams want to hire offensive coaches. But Eberflus sure looks like a good head coaching candidate.

13. Carolina Panthers (3-2, LW: 14)

It’s a little silly to talk about MVP after five games. But it’s clear Christian McCaffrey should win that silly “MVP after five weeks” award. He won’t win MVP for the season because you need to be a quarterback to win these days, but the stretch he’s on right now is special. What a player.

12. Minnesota Vikings (3-2, LW: 13)

We shouldn’t be negative after a win. However, “Kirk Cousins plays well against bad team and Vikings win” isn’t exactly a shocking headline. The Vikings didn’t give him $84 million to tear up the Giants secondary. But, at least this week should be smoother in Minnesota.

11. Dallas Cowboys (3-2, LW: 5)

I’m not really impressed by what the Cowboys did after falling behind 31-3. That was a shockingly bad performance. Things change fast in the NFL, and the Cowboys could look great again by Halloween, but this looks accurate now: They went 3-0 against three bad opponents and were overrated by everyone as a result.

10. Chicago Bears (3-2, LW: 8)

Chase Daniel has had a truly fascinating career. He has received endless praise, often cited as a top-tier backup. He has made more than $34 million in career salary. But he has never played particularly well in the NFL, which seems important. He has seven career touchdowns, five interceptions and an 88.6 passer rating over 10 seasons. Yet, we’re probably still not done hearing how Daniel was totally worth that big new deal he just signed, because he’s such a good backup. I’m not sure there has been another player who has been paid more and received more praise for doing so little. (And yes, I’m not dropping the Bears too much because they were playing in London with their backup quarterback and lost a very close game. They’ll bounce back.)

9. Buffalo Bills (4-1, LW: 10)

One thing to keep in mind: rookie running back Devin Singletary should be a difference-maker for the offense when he gets healthy. He has missed three games in a row. The Bills don’t need a ton of offensive punch either; this defense is really good.

8. Philadelphia Eagles (3-2, LW: 11)

I’m not going to dissect their win over the Jets too much. I suppose it could have been better but they led 14-0 before anyone had even gotten through their first order of crab fries at the Linc. Everyone knew the Jets could play for three weeks straight and not score 14 points. After the last two weeks, this looks like your eventual NFC East champion.

7. Los Angeles Rams (3-2, LW: 4)

Greg Zuerlein has made some huge kicks. He missed, it happens. If that kick is a little bit to the left, we’re praising the Rams for an enormous road win. There’s plenty of time for the Rams to dig out of this relatively minor NFC West hole they find themselves in. In a strange way, the performance in a loss was encouraging.

6. Seattle Seahawks (4-1, LW: 9)

If you see any list of current players who look like future Hall of Fame locks, make sure Russell Wilson is on it. Or else the list doesn’t make sense.

5. Green Bay Packers (4-1, LW: 6)

Since we said many kind words about the Packers on Sunday, let’s add this little concern: It’s troubling how much the Packers rely on Davante Adams. Their pass catchers other than him aren’t good enough. If there’s any receivers available in a trade (Emmanuel Sanders? A.J. Green?) the Packers need to pay whatever it costs.

4. San Francisco 49ers (4-0, LW: 7)

Nick Bosa looks like he was worth every bit of the hype he had at Ohio State, and definitely worth the No. 2 overall pick for the 49ers. He was fantastic against the Browns and looks like a Defensive Rookie of the Year favorite.

3. Kansas City Chiefs (4-1, LW: 2)

I’m not sure Monday was the day to do victory laps over Patrick Mahomes’ expected regression from a 50-touchdown season. He could barely move by the end of the game due to an ankle injury. That affected him. The problem for the Chiefs is they obviously can’t sit Mahomes, but it might take a while before he is totally healthy again if he keeps playing.

2. New Orleans Saints (4-1, LW: 3)

The Superdome crowd chanting Teddy Bridgewater’s name after his touchdown passes Sunday speaks to his popularity. It’s an awesome story he’s authoring. I know the Comeback Player of the Year Award is hyper-focused on a player who suffered a calamity the year before, but giving Bridgewater that award this season would be just fine, given the 2016 injury he overcame.

1. New England Patriots (5-0, LW: 1)

As discussed previously, a team like the Chiefs had to realistically look at the Patriots and their schedule and plan on either winning about 14 games or settling for the No. 2 seed in the AFC. Kansas City’s margin for error in that regard is almost gone. It’s hard to call a team a lock to have home-field advantage through the playoffs before Week 6, but it’s getting harder to come up with a realistic scenario in which the Patriots aren’t the top seed.

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Frank Schwab is a writer for Yahoo Sports. Have a tip? Email him at shutdown.corner@yahoo.com or follow him on Twitter! Follow @YahooSchwab