Robert Saleh discusses Ahkello Witherspoon, D.J. Reed, Marcell Harris, Kentavius Street, and stopping Russell Wilson and the Seahawks

San Francisco 49ers defensive coordinator Robert Saleh spoke with the media on Thursday as the team prepares to face the Seattle Seahawks for the second time in three weeks. Here is everything he had to say.

Transcript provided by the San Francisco 49ers Communications staff.

It seems like since the Bye, CB Ahkello Witherspoon has had three pretty good games in a row. What's been your perspective on him?

"You know, it started before the Bye week, to be honest. I know it doesn't always show up. He had a couple of PIs against the Giants or whatever, but he's been gradually getting a lot better and getting refocused and just understanding that in this league the three most dangerous words are I got it. As soon as you think you've got it, you've lost it. So, he's got great intent and he's got the same mindset he had a year ago. When he plays with that mindset and builds into it, it's a good lesson for everybody. You never have it in this league. Teams are always trying to find you. As soon as you let them find you, they'll find you. He's been good."

How do you think he is at learning that lesson now that he's sort of had similar success at the end of last season and then it didn't necessarily carry over to the first half of the year?

"If he ever thinks he's got it, he'll lose it. Don't take it for granted. Always hone in on your craft. Always study yourself more than you do your opponent and understand what you're putting on tape. Really evolve your game to the third step in our teaching progression, understand what offenses are trying to do to you, not necessarily what they're running. What you're putting on tape, that could expose what you're doing. He's got to continue to grow. That's what makes the great ones great."

You mentioned last week that you see the biggest growth from start one to start two. Did you see that in S Marcell Harris?

"Yeah. We sat up here and talked about it last week, what we would like to see most, and that was his tackling. Finished some of the tackles that he had missed against Seattle, and he did. So, now he gets to see Seattle again. They've got three really, really good backs and so it's the same thing. How much more can you progress? Now, he's got to go get the ball. Just continue to keep getting better."

What do you think clicked for DB D.J. Reed Jr. on Sunday?

"D.J., he's a good football player. He had an opportunity to go out there and play. He's an instinctive player. He's had some opportunity throughout the season to go play and I'm excited for him. I'm glad he got his opportunity, and he showed up."

We were asking players on your defense yesterday, what's the key to stopping the Seahawks? They said it's the same thing. You've got to stop the run, you've got to set the edges. What's the key in that facing them this week? What do you guys have to do?

"It's the same. They had seven carries for over 110 yards when they broke our edges. So, it's gap discipline and making sure that you set edges on the defense with great lockout and extension. Keep the ball in the chute and go tackle them. When you tackle, you've got to arrive violently. Their other 22 carries went for 50-something yards. They're a very, very good running team. Their three backs are probably the most underrated trio of backs in football, in my opinion. [Seattle Seahawks QB] Russell [Wilson], obviously, is no slouch. So, they've got a dynamic offense. They look pretty good. They've got a great philosophy to what they're doing right now. It's going to be an exciting challenge."

What goes into stopping Russell as a runner and how does he make that rushing attack tougher to stop?

"From a running standpoint, mostly with Russell, when he drops back to pass and the play breaks down, he extends plays, he gets off-schedule, that's where Russell is his most dangerous. Obviously, he could always tuck it and run, which he does. But, he's most dangerous when he goes off-schedule on a pass play. You've got to get great pocket push. You've got to have great lane discipline in your rush lanes, and the big thing is you've got to have extension and lockout, even in pass plays where if you let them into your body where they can tug and hold you, he's going to escape. They've got an art to it, the way they teach their scramble rules, the receivers and all that stuff. They've been doing it for a long time and they're really efficient."

Their run game really took off when they started using that heavy package with Seahawks Seahawks T George Fant in there more. What kind of challenge is that? How do you attack that when you see that?

"He's a big boy, so it's not like a normal tight end that you can just knock back and ragdoll. He's an added element where he creates push and strain. It's a good element. They're very deliberate in what they're trying to accomplish. They're very effective at it, too."

What did you see when you watched Marcell Harris on tape in 2016 at Florida?

"Violence, speed, no hesitation. He's a very physical defender. He's showing what he showed on tape. He's got a long way to go, for sure, but he's exciting to work with."

Re-watching the draft videos, some of the commentators said he might have been a third or fourth-round pick had he been healthy. Is that a similar assessment to what you had?

"I don't know. He could easily have just balled out, too, and been a first-rounder. You never know how those things turn out, especially since he never got the test. I don't know about all that. I do know that we really liked his tape and felt like he was someone that could contribute to what we're trying to get done."

Now that you're seeing DL Kentavius Street on the field for the first time, what have been your first impressions of him and if you could forecast 2019 where he is going to fit in?

"I'm not ready for the second part of the question. But, I am excited to get him out there. He's excited to get out there. There's really no expectation. Just get out there, go through drills. He's still trying to feel and understand the drills. Think about it, he hasn't run a drill in over a year. So, just to give him that ability to just get in, go through the process and progress. Then, next year, we'll have a very clear idea of where he fits."

He's a bigger bodied guy.

"He is, he's bigger bodied, great athleticism, a lot of explosiveness, at least from tape. All of that stuff will come back as he gets more comfortable with his knee. But, what he showed on tape in college was a lot of explosiveness, great body balance, good lean quickness and the big thing is strength. The guy is very strong."

How pleased were you with the effort against Denver Broncos RB Phillip Lindsay and how do you replicate it?

"I'm always happy with the way our guys play in terms of effort. I'll never question our group's effort. It's just the mindfulness of what we were trying to get done from a run-game standpoint, everyone being disciplined and doing their job. That was kind of the key with Denver, getting back to the fundamentals and what makes us good. So, it's no different. Every once in a while, it can slip and when you slip against a really good team like we did two weeks ago, bad things happen. So, just reconnecting our fundamentals and what we teach and being disciplined as individual football players, doing your job. So, effort-wise, it's always there. Our guys play hard. They don't know any better. So, I'm excited to see them do it again."

You mentioned that the running back trio there in Seattle is underrated. What have you seen from them, specifically from Seattle Seahawks Rashaad Penny who has had an increase in production the last few weeks?

"Rashaad is a dynamic runner. You can see the talent, for sure. All of them, they've got speed to break it outside. They've got strength to push it inside and they break tackles, they make people miss. They've got breakaway speed. They complement each other really well and you could tell that they feed off of each other in terms of what each other is getting. So, it's a cool group they have, to be honest with you."

Going back to Ahkello, I don't know what options you would have had for this, but would it have been better to create competition for him in the offseason as far as, 'Hey, you're not necessarily our starter?'

"Competition is always good. It's healthy for everyone from top down. It doesn't matter. Competition is the greatest motivator. The only people who don't care about competition are those who are internally motivated. To answer your question, yes. And that's all the way throughout the roster, through the coaching staff, everybody. It doesn't matter."

With Harris playing well and with S Jaquiski Tartt having started his last game at free safety, is that a combination that you're looking at for next year, that safety duo of Harris and Tartt?

"We're trying to get guys on the football field to see where they fit and how they can play and how they can step up. Trying to see who can break the door down in terms of adding to the competition for next year. So, Marcell showed up, did a really, really good job and he's making a case that he belongs in the conversation for next year at whatever position. And same thing with Tartt. Once the season is over and we can go back and evaluate all of the tape, all of those decisions will be made. But, trying to add competition as much as we can."

We saw him run down Seattle Seahawks WR Tyler Lockett on the kick return in that game. It seemed to show his speed. Does he have the speed to play that free safety spot?

"He's got great speed. Tartt, if you remember the first game of the year last year, he had that one-handed interception, he covered redline to redline had a lot of ground covered. So, him playing the middle is definitely a possibility. But like I said, he's a pretty darn good strong safety too. So, who steps up and how the roster shakes out and all that stuff, that'll be determined once OTAs comes around."

After Sunday's game, head coach Kyle Shanahan mentioned the energy that D.J. Reed and Marcell Harris played with. How is that energy that they bring a little bit different?

"It's that joyful youth, right? You know, they're out there, they're playing and now the challenge is to maintain it. Going back to what I said earlier, don't ever assume you've got it and understand that it's a blessing to be in the positions that we're in and go out and play ball. The energy is always good because everyone feeds off of each other's energy. [LB] Fred Warner had great energy. [DL DeForest Buckner] Buck was playing with great energy. The whole defense was feeding off of each other and when one guy makes a play, the other person wants to make a play. It's just a trickle-down effect. So, the challenge is consistency being the truest measure of performance. We've got to go do it again."