What a wild Week 3. The San Francisco 49ers sit atop the NFC West, thanks to a second-half collapse by the Rams and a Seahawks wire-to-wire loss to the Commanders.

Every game but two was decided by one possession. That’s the NFL in a nutshell. Whatever you learned about a team last week, forget it. It doesn’t apply to the following week.

A lot of chaos occurs over a 60-minute sample size. The variance will have you thinking you’re in for a comfortable victory, like the Rams and 49ers probably figured in the first half. But the other team gets paid, too. In San Francisco’s case, they handled the adversity and answered every time with a score.

Oddsmakers are expecting another nailbiter in Week 4. The 49ers opened as 2.5-point favorites over the Broncos at FanDuel Sportsbook, with the total set at 46.5.

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The 49ers are the first team not to allow a sack in three weeks since the 2015 Bengals. It’s the first time in franchise history during that stretch since 1979. That is a Brock Purdy stat.

Heading into Week 3, the Broncos were ninth in the NFL in pressure percentage. Trent Williams should be OK with a stinger, but the Niners will be taking a big step up in class in their opponent.

The Rams racked up a bunch of yardage, but they ran 82 plays. Perhaps that’s the key there for Kyle Shanahan: Possess the ball and keep your injury-riddled defense off the field.

Had it not been for Davante Adams’s pristine route running, Matthew Stafford might’ve struggled even more than he already did.

Mike Evans looked to be in a lot of pain on Sunday. If he can’t overcome his rib injury, the 49ers wide receiver corps will be at a disadvantage, especially against an angry Pat Surtain. We did see cornerback Riley Moss get beaten deep on a double move. Perhaps that’s where Jacob Cowing can make an impact, much like he did as a rookie against the Chiefs?

If you’re wondering why the line is so short, we just mentioned injuries to Williams and Evans. Take away Nick Bosa, and you’re down three of the team’s best players. Dre Greenlaw means Garret Wallow plays an entire game.

The Broncos are above league average in passing success rate and EPA per pass. We did see the Rams run the ball effectively against Denver. But as Sean McVay tends to do, he got pass-happy.

Fifty-five (!) passing attempts for Stafford on a day when your starting running back was averaging nearly six yards per carry cannot happen, not when you’re relying on YOLO balls down the field.

I don’t think Kyle Shanahan will be as reluctant to include Christian McCaffrey in the game plan, especially after the way McCaffrey just ran the ball in Week 3.

But we can’t ignore the other side of the ball. The total on the game being closer to 50 tells us the 49ers are going to get theirs, but Bo Nix should move the ball as well.

It took Denver until the third quarter to find the weaknesses in the Rams’ defense. Arizona moved the ball in the first half, but didn’t start converting those opportunities into touchdowns until the second half. Historically, the 49ers have done well against bigger wideouts but struggled against speedy types.

Jaylen Waddle and running back R.J. Harvey are major challenges for a defense that’ll likely be short-handed in the pass rush again. Can they be a bend-but-don’t-break unit for longer than a half, or will it be a game where Purdy has to shoulder the load once again to ensure his team comes out on top?