There aren’t many San Francisco 49ers doubters left, but they were validated Sunday.

The Atlanta Falcons were 4-9 before a date at San Francisco. The 49ers were one of two 11-2 teams in the NFL. And the Falcons won.

Atlanta barely got a game-winning touchdown with two seconds left, but it wasn’t a fluky win. Led by the incomparable Julio Jones’ 134 yards, the Falcons played with the 49ers the entire game. The stats were about even. Atlanta, which was 1-7 at Halloween, didn’t back down.

Does losing at home to a moribund Falcons team expose the 49ers? Probably not, though it is concerning.

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The 49ers had a good excuse for being flat. They played a 60-minute game at the Baltimore Ravens two weeks ago, losing on a field goal as time expired. Then they went back on the road, played another 60-minute game against the New Orleans Saints in Week 14, and won on the final play. That’s a tough stretch. That will take something out of a team, and it’s human nature to let down a bit. People will believe because the 49ers are professionals they should be at the same emotional level for every game, but it’s understandable why they would relax against a Falcons team everyone figured they’d beat. It happens.

Yet, maybe there are some things that could be negatives the rest of the way.

Jones’ big game was the second straight huge performance by a No. 1 receiver against the 49ers. New Orleans Saints receiver Michael Thomas also had a big game against San Francisco in Week 14. The 49ers clearly missed cornerback Richard Sherman, who was out with a hamstring injury. Sherman could miss the rest of the regular season. That’s a concern, at least until Sherman gets back.

The lack of distribution on offense Sunday was also odd. George Kittle had 13 catches for 134 yards. Everyone else had nine catches for 66 yards combined. And 29 of those yards came on Deebo Samuel’s only catch. No other 49ers had more than 11 yards receiving. That hasn’t been a glaring problem, though the 49ers aren’t great at receiver. Kittle is perhaps the best tight end in football, but the 49ers are going to need more than him. There’s no guarantee that will happen with this receiving corps.

One bad loss doesn’t change much for the 49ers. They can win the NFC West with two more wins, including one at Seattle in Week 17. They still have a good shot at the No. 1 seed in the NFC. In the big picture, the loss against the Falcons might not mean much. But the 49ers won’t want to have another performance like that for the rest of the season.

Here are the Power Rankings after Week 15 of the NFL season:

32. Cincinnati Bengals (1-13, Last Week: 32)

Another loss Sunday was good for the Bengals. They play at the Dolphins this weekend, and they have a two-game cushion for the No. 1 pick. Losing that pick just to get to three wins this season would not be smart.

31. Detroit Lions (3-10-1, LW: 29)

Again, yes, the Matthew Stafford injury affects a lot of things. It’s not the reason Jameis Winston had 308 yards at the half or 458 for the game. Matt Patricia’s defense is terrible and that has to factor in the decision of whether to give him a third season.

30. Washington Redskins (3-11, LW: 30)

Dwayne Haskins had by far his best game. He had 261 yards, two touchdowns and a 121.3 passer rating. If Haskins can look like that the last two games, Washington should be optimistic about him heading into the offseason.

29. Miami Dolphins (3-11, LW: 28)

DeVante Parker last week signed a four-year extension worth about $40 million with an $8 million signing bonus. Given Parker’s breakout and his first-round draft pedigree, he seemed to settle for a lot less than he could have gotten as a free agent. Maybe there was some loyalty involved, since Miami stuck by him when everyone thought they should throw in the towel, but either way it’s a fantastic deal for the Dolphins.

28. New York Giants (3-11, LW: 31)

Speaking of wins that could haunt a team for a decade or so ... look, it was great for Eli Manning to get his proper sendoff, and all NFL players and coaching staffs want to win. But the Giants, who play against the similarly terrible Redskins this week, might have cost themselves the chance to draft Ohio State defensive end Chase Young, who has the look of the NFL’s next dominant pass rusher.

27. New York Jets (5-9, LW: 27)

How is No. 3 overall pick Quinnen Williams doing? It could be better. He has just 24 tackles and 1.5 sacks, though he was unlikely to post huge numbers as a rookie interior lineman. NJ.com gave him a B-minus. He ranks No. 46 in Pro Football Focus’ grades among interior linemen with 400 snaps. There’s a lot of time for Williams to grow, but he hasn’t had nearly the impact the Jets were hoping for.

26. Carolina Panthers (5-9, LW: 24)

It seems the Panthers will turn to rookie Will Grier at quarterback this week. The Kyle Allen story turned so fast. This is not a team that can dump Cam Newton in the offseason, unless they figure out a really good Plan B.

25. Jacksonville Jaguars (5-9, LW: 26)

For as bad as the first three quarters looked, the Jaguars will remember rookie Gardner Minshew II leading the team to a comeback win in the fourth quarter. He threw two touchdowns in the final six minutes, including the game-winner with 31 seconds left. The Jaguars should at least give Minshew the full 2020 season as starter. They might have hit a draft grand slam in the sixth round.

24. Arizona Cardinals (4-9-1, LW: 25)

I didn’t get why the Cardinals traded for Kenyan Drake in a lost season but it looks good now. They must have seen that Adam Gase and the Dolphins criminally underused Drake. Drake becomes a fascinating free agent, though you have to assume the Cardinals try to resign him before he hits the market.

23. Los Angeles Chargers (5-9, LW: 22)

The Chargers have mostly been competitive and adept at losing in insane ways. Sunday was just bad. They were sloppy with the ball and got blown out at home by the Vikings. That’s the first time you watched the Chargers and wondered if it’s time to make some significant changes.

22. Oakland Raiders (6-8, LW: 21)

I get that the Raiders had a tough early schedule and they look like they’re out of gas. But that was still one incredibly bad loss. Forget that it was the final game in Oakland for the team, it’s the kind of loss that further dissolves any positive vibes the team could have had heading to Las Vegas for next season. Nobody will remember that promising 6-4 start this year.

21. Atlanta Falcons (5-9, LW: 23)

Has Dan Quinn saved his job? On one hand, wins at the Saints and 49ers are truly impressive and a sign of what the Falcons can do at their peak. On the other, why have the Falcons so infrequently hit that peak this season?

20. Denver Broncos (5-9, LW: 20)

Von Miller’s words after Sunday’s loss are being dissected in Denver: “I really don't even know what to say. I don't know how we got to this point. I don't know how we win like this, I really don't. ... It just defeats my soul to go out there and play the way we play and lose the way we lose.” It’s easy to understand his frustration. Miller doesn’t have endless prime years left. It’s a situation worth keeping an eye on this offseason.

19. Cleveland Browns (6-8, LW: 19)

Bad to worse. The Freddie Kitchens-Jarvis Landry dustup could have been just one of those random sideline moments that gets overblown ... but it seemed like more than that was going on.

18. Indianapolis Colts (6-8, LW: 18)

The Colts have just run out of gas. It’s disappointing because they were a very interesting team coming into the season, at least before Andrew Luck’s retirement, but hopefully they can rebound next season.

17. Philadelphia Eagles (7-7, LW: 17)

Miles Sanders’ 172-yard game is probably a sign of things to come. But as a whole, the Eagles still look awful. Not that the Cowboys are great, but Philadelphia doesn’t look like they can win that NFC East title showdown on Sunday.

16. Chicago Bears (7-7, LW: 14)

The Bears are out of the playoff race, and now we can dissect what Mitchell Trubisky really meant when he seemed to criticize Matt Nagy and the play-calling. It’s going to be a long offseason in Chicago.

15. Tampa Bay Buccaneers (7-7, LW: 16)

The Jameis Winston story is fascinating. The Buccaneers are probably going to pay him at this point, but will he get the enormous deal most quarterbacks get? Will the Bucs have to franchise tag him? Winston can be fantastic and terrible all within the span of a few plays, but he’s never boring.

14. Los Angeles Rams (8-6, LW: 11)

The Rams are all but dead now, and Sunday’s miserable performance said so much about them. This has just been a disappointing team in every way, though they’d occasionally tease us with a good game and we’d wonder if that was the sign of a turnaround. Nope. It won’t get easier with Jared Goff’s contract weighing them down, either.

13. Pittsburgh Steelers (8-6, LW: 13)

If the Steelers make the playoffs — and they’re still right in the mix for that, even with Sunday’s loss — T.J. Watt will get some NFL defensive player of the year consideration. He has the top Pro Football Focus grade among all edge defenders. His 13 sacks are fifth in the NFL and he has made a bunch of big plays. He could get some more votes with a big finish.

12. Dallas Cowboys (7-7, LW: 15)

I’m with Terez Paylor: The Cowboys’ win Sunday didn’t prove much. But at least it was something. They’re better than the Eagles and I assume they’ll win in Philly and take the NFC East this week. And the talent is there to actually do something in the playoffs. But the Cowboys have been awful most of the season, so I’m not counting on anything beyond beating a similarly awful Eagles team.

11. Tennessee Titans (8-6, LW: 10)

The Titans’ loss puts them in a position in which they might have to win against New Orleans and at Houston the rest of the way to make the playoffs. Not easy. It’s not shameful to lose to the Texans, even at home, but that was a really damaging loss.

10. Houston Texans (9-5, LW: 12)

Sunday’s win practically ensures a playoff spot and should end up being the reason they win the AFC South. The good part about a wholly inconsistent team like the Texans is they will have their good days too.

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

The Bills aren’t complete yet, but we’ve been waiting for a team to step up and finally challenge the Patriots in the AFC East. It seems Buffalo will take that shot, starting next season. The Bills are building something pretty interesting.

8. Minnesota Vikings (10-4, LW: 8)

The news wasn’t too bad on Dalvin Cook’s injured shoulder. It appears he could play in Week 16 against the Packers. The Vikings need that game to keep any hope of winning the NFC North alive, but it’s probably moot anyway since all the Packers need to do to win the division title is beat the Lions in the finale.

7. Seattle Seahawks (11-3, LW: 7)

The Seahawks are really getting beat up on defense. We’ll see who’s healthy enough to play this week and more importantly, if they can be mostly healthy for the all-important Week 17 games against the 49ers.

6. Green Bay Packers (11-3, LW: 6)

Marquez Valdes-Scantling had an inexplicable drop on a wonderfully thrown deep pass by Aaron Rodgers early in the game Sunday. Rodgers may not be quite the player he once was at his peak, but aside from Davante Adams, who is helping him?

5. New England Patriots (11-3, LW: 5)

Julian Edelman is dealing with numerous injuries, and had just a pair of catches for 9 yards on Sunday. The Patriots’ offensive struggles have been discussed endlessly, and they’re not getting better if Edelman can’t be effective through his injuries.

4. Kansas City Chiefs (10-4, LW: 4)

We get used to Patrick Mahomes doing special things, and the Chiefs’ win over the Broncos didn’t get too much attention because Denver wasn’t competitive, but Mahomes made it look easy in a snowstorm. He had 340 yards passing. It was one of the more impressive bad-weather performances you’ll see.

3. New Orleans Saints (11-3, LW: 3)

Quite simply, Drew Brees is incredible.

2. San Francisco 49ers (11-3, LW: 2)

Emmanuel Sanders has been all or nothing since the 49ers traded for him. He has games of 157 and 112 yards. He hasn’t had more than 41 yards in any other 49ers game, and had just 9 yards in the loss to the Falcons. The 49ers need more consistency from Sanders. Also, I’m not moving the 49ers down because over the entirety of the season they’ve been better than any team listed behind them.

1. Baltimore Ravens (12-2, LW: 1)

If it wasn’t for Travis Kelce, Mark Andrews would have a good argument as the AFC’s best tight end. He has 58 catches, 759 yards and eight touchdowns. His 13.1-yard average is very good for a tight end. He and Lamar Jackson will be a potent combination for a long time.

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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