Biggest Takeaways from San Francisco 49ers' Week 16 Loss

Week 15, the San Francisco 49ers committed 11 penalties for 98 yards against the Cincinnati Bengals, and the very next week they committed 11 penalties for 65 yards against the Detroit Lions. Seven of those flags were neutral-zone infractions or offside penalties.

The Niners kept making the same mistake.

An NFL team shouldn’t make the same mistake over and over this late in season. The Niners should have learned from their mistakes by now. But, they have committed 46 penalties the past five games—9.2 every week. They are an undisciplined team.

That’s the first big takeaway from the 49ers’ 32-17 Week 16 loss to Detroit on Sunday. Here are five more.

Ian Williams May Have Priced Himself Out of the 49ers’ Market

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The highest-graded player on the 49ers this season, according to Pro Football Focus, is nose tackle Ian Williams.

During the past five weeks, Pro Football Focus has given Williams a grade of plus-21.4—third-best in the NFL among nose tackles and defensive tackles. The only interior defensive linemen with higher grades the past five weeks have been Geno Atkins of the Cincinnati Bengals and Aaron Donald of the St. Louis Rams.

Williams will be a free agent this offseason and will get big bucks. But from whom? How much money will the 49ers want to give a defensive lineman who doesn’t rush the passer and plays only in the base defense? Williams may have priced himself out of the 49ers’ nose tackle market.

Jaquiski Tartt May Need to Move to Linebacker

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Opposing offenses have picked on rookie Jaquiski Tartt since he became the 49ers’ starting strong safety Week 7.

Tartt has given up 23 catches as the starting strong safety. Against the Lions on Sunday, he gave up three catches for three first downs and missed three tackles in pass coverage. He seemed lost trying to cover the deep areas of the field.

Tartt seemed much more comfortable the first six weeks of the season when he was the team’s dime back—essentially an inside linebacker in the dime defense. Tartt lined up in the box and covered the other team’s tight end man to man most of the time.

As the dime back, Tartt gave up only nine catches, and six came in one game. The other five games he gave up three catches for 39 yards.

The Niners should consider moving Tartt to inside linebacker full time next season.

DuJuan Harris Should Be the Primary Running Back Week 17

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DuJuan Harris split carries with Jarryd Hayne in Week 16, even though Hayne averaged 3.0 yards per attempt against the Lions and Harris averaged 6.6.

Harris probably didn’t play every snap because he couldn’t have known every protection in the passing game—he signed only last week. He was still learning.

Next week, he should know enough to play most of the game. Former Niners starting running back Shaun Draughn picked up San Francisco's playbook in a couple of weeks after signing with team—Harris should be able to learn the playbook quickly too.

The Niners need to see what they have in Harris. Could he be the team’s scatback next season? He seems more explosive than Draughn.

The Offensive Line Is Improving

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DENVER, CO - AUGUST 29: Offensive tackle Trenton Brown #77 of the San Francisco 49ers looks on from the bench against the Denver Broncos during preseason action at Sports Authority Field at Mile High on August 29, 2015 in Denver, Colorado. The Broncos de

The 49ers’ starting offensive line to begin the season had Joe Staley at left tackle, Alex Boone at left guard, Marcus Martin at center, Jordan Devey at right guard and Erik Pears at right tackle.

Staley and Boone played well. But Pears struggled at right tackle, and Martin and Devey were disasters. The offensive line was subpar.

Since then, Martin has suffered a concussion, and Devey has gotten benched. The starters Week 16 were Staley at left tackle, Andrew Tiller at left guard, Daniel Kilgore at center, Erik Pears at right guard and Trent Brown.

All of a sudden, the O-line is pretty good. Pears seems much more comfortable at guard than at tackle, Tiller is a mauler and Brown may be special. The Niners may not have to spend their first-round pick on an offensive lineman next year.

Blaine Gabbert Needs to Be More Aggressive

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Blaine Gabbert has done certain things well this season: He won a couple of games and posted numbers better than those of Colin Kaepernick despite playing with inferior players.

That doesn’t mean next season Gabbert should be the starting quarterback for the 49ers or any team for that matter. Gabbert doesn’t seem aggressive enough to be a starting quarterback.

Since becoming the starter Week 9, Gabbert has posted a third-down passer rating of 72.1, and the Niners have converted just 23.3 percent of their third downs. Those numbers are unacceptable.

Unless Gabbert improves drastically on third down, the Niners probably should spend their first- or second-round pick on a quarterback next year.

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Stats courtesy of Pro Football Focus unless otherwise noted.