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49ers Notebook: Shanahan explains Aiyuk situation, Warner talks issues with run defense

© Darren Yamashita-USA TODAY Sports

If there’s one thing you can count on from Kyle Shanahan, it’s being particular. Shanahan is as specific as it comes in terms of what he demands from his players, especially his skill position players. He made a statement on Sunday when he benched third-round pick Trey Sermon, and star receiver Brandon Aiyuk was in an effective timeshare with Trent Sherfield, but not targeted a single time.

Unhappy with Aiyuk?

After Sermon’s benching, the other story of Sunday’s game, at least as far as conscious personnel decisions was concerned, was Aiyuk’s lack of involvement. Aiyuk played 26 offensive snaps to Sherfield’s 27, but Aiyuk wasn’t targeted a single time. Shanahan said after the game he would have liked to get him more snaps, but didn’t exactly pretend like there was no way to get Aiyuk involved.

The 49ers did plenty with Aiyuk last season to manufacture easy touches, whether that was on screens, end-arounds, or just shorter patterns.

None of that was visible on Sunday, when Sherfield was targeted three times, resulting in two receptions for 23 yards and a touchdown. Aiyuk wasn’t targeted once.

Shanahan pointed both to Sherfield’s performance in training camp (which was outstanding) and Aiyuk’s lack of involvement due to a hamstring injury after Sunday’s game, and commented on the situation further on Wednesday.

“Trent’s been a hell of a football player since he’s been here,” Shanahan said. “Aiyuk’s been a little inconsistent because he’s been in and out with the injury… I’m happy with Aiyuk. It’s nothing against Aiyuk. I’m just also happy with Trent, too. And I think both of them can continue to get better…

“It’s not like we’re punishing Aiyuk or something because Trent got even reps with him or we rotated those guys. I’m not gonna sit here and say [Aiyuk]’s got to do A, B and C, to get back out there. It’s more, we’ve been practicing the last month and one guy’s been there every day and then the quarterback’s got a lot of confidence in him, I do too. But if he wants to be out there every single play, he’s got to be a lot better than the guy behind him.”

So, what should be made of this? There’s clearly an element of tough love here from Shanahan. Few coaches are as harsh on their receivers as Shanahan is, and he also demands blocking excellence and commitment, where Sherfield is undeniably ahead of Aiyuk. So from Shanahan’s perspective, if one guy has been healthy and is a better blocker, he deserves snaps.

Now, the other component here is that Aiyuk is probably the most talented receiver on this team, and it would be a pretty drastic move and miscalculation to not get him consistently involved in the offense. It’s still too early to imagine a scenario where Aiyuk isn’t a major component of the offense, but Shanahan is certainly demanding more from him.

Run defense issues

One area of major concern for the 49ers against the Lions was their run defense. There were myriad plays where one of D’Andre Swift or Jamaal Williams gashed the 49ers, and they almost solely came up the middle.

A few things were clear when reviewing the tape; the 49ers desperately miss Javon Kinlaw, and Zach Kerr struggled mightily in his stead. The Lions also had some very well-designed run plays, and have a physical, athletic offensive line, especially as it pertains to the run game.

Some of those plays could have been limited, or prevented from becoming “explosives” as coaches like to term them, if there was more discipline from the linebacker corps, specifically from both Dre Greenlaw and Azeez Al-Shaair.

Both Greenlaw — who suffered a groin injury — and Al-Shaair had some eye-popping plays in which they displayed their speed, range, and tackling ability. But both of them were also caught out multiple times when they displayed poor eye positioning and were either manipulated by the flow of the offensive line or by Jared Goff’s eyes.

There were occasions when they took bad, over-aggressive angles to the balls, and let potential short gains become chunk plays, and often left safeties out to dry. That’s what happened on the short pass to D’Andre Swift, which became a 38-yard touchdown. Al-Shaair played it far too aggressively, rather than being patient and slowing the play down, and let a Lions blocker take him out of the play. That left Jimmie Ward in a one-on-one, which he lost, and the Lions scored.

Linebacker Fred Warner said there was too much freelancing going on against Detroit.

“Those busted runs are all technique issues that we’re gonna get cleaned up,” Warner said. “We do preach being physical, being aggressive, but also being assignment sound, being smart players. There should never be a situation where we’re all flowing, or like out of the gap, trying to just freelance or make a play where they will have an open gap or anything like that. So we’ve just got to make sure we’re assignment sound, fundamentally sound, and we’ll be good.”

You do expect a defense as talented as the 49ers to clean up those mistakes, but for the linebacker group to be the one making mistakes, with former linebackers coach and former Pro Bowl linebacker DeMeco Ryans now at the helm as defensive coordinator, it does raise some eyebrows.

Ryans has stressed that he wants to keep things simple for his players so they can “play fast.” Perhaps… they’re playing too fast?

Injury updates

Those mistakes are magnified by the fact that the 49ers may still be without Javon Kinlaw this week, as well as Emmanuel Moseley, and possibly Greenlaw and others. Here’s what the team’s injury report looked like on Wednesday in West Virginia.

Did not participate:

DT Javon Kinlaw (knee)

CB Emmanuel Moseley (knee)

LB Dre Greenlaw (groin)

DL Arik Armstead (hip/adductor)


DE Dee Ford (minor ankle sprain)

LB Marcell Harris (oblique)

Shanahan said he’d “be surprised” if Armstead doesn’t play, but that they’re being cautious after his hip tightened up on him following Sunday’s game. As far as Kinlaw, though, it’s not as straightforward.

He said Kinlaw’s knee injury sustained against the Cowboys last year was “a pretty bad injury” and that his recovery hasn’t exactly gone according to plan.

“He got it cleaned up but it still hasn’t healed quite as right as we want,” Shanahan said. “So, it seems like when he [was] gone, it’s started to affect him. So, hopefully taking it easy these last 10 days or so, it’ll start to get better and we’ll see how it goes day to day.”

Moseley, meanwhile, is not expected to be out long term, Shanahan said, and will be re-evaluated on Thursday.


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