What are the 49ers' biggest concerns with 2 weeks remaining in the regular season?

The 49ers are riding the highest of highs with two weeks remaining in the regular season. San Francisco is in the top five for most NFL power rankings you read. But since Week 10, they have dwarfed the rest of the NFL in many categories.

The Niners are first in total team DVOA, second in offensive DVOA to the Chiefs, but have the best passing DVOA by a wide margin. The 49ers’ offense is also third on the ground. So they can score on you by running or throwing and are far and away the top defense.

So, what are the team’s biggest concerns with two weeks remaining in the regular season?

Offensive line is no longer a worry

CBS Sports’ Jeff Kerr had a takeaway from each team’s Week 16 performance and applauded the 49ers' offensive line against a stingy Commanders front four:

The offensive line shined against a tough test: San Francisco deserves a ton of credit for holding Washington’s defensive front in check Saturday, as the offensive line was credited with allowing just one sack and three pressures on the day.

Trent Williams didn’t allow a single pressure in 26 pass-blocking snaps while Spencer Burford allowed just one sack and one pressure in the win. The biggest aspect was keeping Brock Purdy upright, which is why he’s been as efficient as he’s been in those three starts. If the offense keeps Purdy from under duress, the 49ers will be a huge problem in the postseason.

Since Week 10, Trent Williams has been PFF’s second-highest graded offensive lineman, as he’s allowed one sack and quarterback hit and been penalized once. But it’s not just Williams.

Center Jake Brendel hit a rough patch for a couple of games, but he hasn’t allowed a sack since Week 10 nor missed a game all season. Here’s Kyle Shanahan on Brendel’s play this season:

“I think Jake’s played really well. We were really happy with him last year, just watching him throughout practice and everything. [Former C] Alex [Mack] stayed healthy all last year, so he didn’t get much game experience, but we went into this year with him as our guy. And you never know until they get out there and he’s been able to make it through this whole year. He’s been able to stay healthy. He’s done a great job with the calls, getting us in the right protection schemes and blocking schemes and he’s been able to make some plays too. He’s helped us in both the run and pass game and I’ve been really excited with him as one of the leaders here on our team too.”

First-year starters Aaron Banks and Spencer Burford are learning on the fly without serving as liabilities. At the same time, Mike McGlinchey has also kept a clean sheet from a sack perspective since Week 10 but has allowed three quarterback hits.

Cause for concern in the secondary?

The 49ers' secondary proves they’re not unflappable each week. For what feels like the fourth or fifth game in a row, there was a miscommunication that led to a touchdown that involved Talanoa Hufanga.

The importance of Mooney Ward goes without saying, as he’s been as competitive and trustworthy as the 49ers could have hoped. Jimmie Ward isn’t too far behind, but opposing offenses are pinpointing San Francisco’s safeties and Deommodore Lenoir more and more.

Since Week 10, Tashaun Gipson and Talanoa Hufanga are PFF’s 88th and 98th graded defensive backs, respectively. Hufanga has allowed a whopping five touchdowns during that stretch. Gipson has played relatively well, but the long pass last Saturday that Terry McClaurin caught that looked like it was on Samuel Womack resulted from Gipson’s overaggression.

Teams are taking shots down the field and attacking the 49ers at the numbers and down the seams — a place where even the mighty Niner pass rush can’t help.

We will learn a lot about Lenoir during the playoffs. He had a rough go at it against Jahan Dotson. Lenoir hasn’t been underwhelming by any stretch, especially considering the situation he was thrown into. But it’s the NFL, and he’s been a clear target recently. Lenoir’s only allowed a 58.8 percent completion percentage. But as we saw against the Commanders on the first drive, he’s been the beneficiary of good luck.

Inevitable depth

Deebo Samuel remains out, but his return, along with running back Elijah Mitchell’s, appears imminent. The 49ers lost a defensive tackle for consecutive weeks but also returned starters Arik Armstead and Javon Kinlaw.

It’s been no Jimmy Garoppolo, no problem offensively. San Francisco has weathered some in-game losses, such as Mooney Ward for a half against Washington. You know, at some point, the 49ers' injury luck will be tested once again. But the team has withstood and overcome injuries all season and for much of Shanahan’s tenure. If there was a battle-tested team, it’s this one.

It’s Kyle, not Brock

We have a four-game sample size to evaluate Brock Purdy. Since Week 13, Purdy is fifth in adjusted accuracy. That tells you the ball isn’t hitting the ground, and the offense is staying on track. We know Shanahan will scheme receivers open, but will the quarterback do his job? So far, so good.

As with most quarterbacks, Purdy’s numbers plummet under pressure. He’s middle of the pack in completion and turnover-worthy throw percentage but is third-worst in adjusted accuracy.

What’s encouraging is Purdy has one of the highest passer ratings and is fourth in yards per attempt, meaning he’s getting explosive plays to offset his negative ones.

We know that come playoff time, teams, just as they did when Jimmy was under center, will make Purdy beat them. So far, Purdy has answered the bell. He hasn’t faced a ton of adversity yet, and unfortunately, we won’t know how he deals with it until he’s put in a difficult situation.

What are your biggest concerns with the playoffs two weeks away?