San Francisco 49ers defensive coordinator Robert Saleh spoke with reporters after Thursday's practice as the team prepares for its Week 15 matchup against the Atlanta Falcons. Here is everything he had to say.

Transcript provided by the San Francisco 49ers Communications staff.

When you look back on that Saints game, what was your takeaway from the defensive point of view, missed tackles, blown assignments?

"That team's got so much speed and of course a Hall of Fame quarterback. If you're not precise, and I'm talking about myself, too, not just players, but if we're not precise with the way we're coaching and the way we're executing, they can embarrass you in a heartbeat. Those first four drives didn't go the way we wanted, obviously. We started playing good football. We had six straight drives where we were getting off the field, two to finish the half, and then the second half started out really good. It felt like we were getting into a groove. We got off the sudden change, held them to a field goal, got the ball back on the next drive. They had a 10-play, 50-yard drive that led to a field goal and then on that fourth drive, which I think was probably the biggest drive of the game, they took over at midfield, we kept points off the board and they went for it on that fake punt, which led to a two-score game. On those last two drives, we've got to be able to make a play when it presents itself. We had about three opportunities there to get the takeaway that would end it, and it just didn't work out for us. I was pleased with the way we had that good ball, you know we settled down, we were playing good ball, but it just goes to show it's a good learning lesson for those guys. When you're playing a Hall-of-Fame talent and they've got all that speed on defense, for coaches and players, we have to be as precise as possible or they can embarrass you."

What was it like for you during that whirlwind first half, I guess the whole first half? Not only are they racking up yards and points against you, but then your offense gets the ball, scores one play, two plays. How do you guys settle down in the third quarter? I figured that you probably had some time to adjust at halftime it seemed, but what was it like during that first half whirlwind?

"First, I love the offense answering the way they were. And so, the challenge for us to get on the field and answer and get the ball back for our offense when they're humming the way they were, it's one of those just get them the ball, they'll go score. Obviously, not a lot of time to adjust with the things, but to be honest with you, from a schematic standpoint, it wasn't anything that they were doing that was hurting us. It was just us executing the play and be more precise in what we were doing. The tackling, getting yourself closer to the tackling point, taking away more grass, setting edges better so it's not such a hard tackle for the guy trying to work inside out. There were just little details where all 11, including coaching staff, we could've just done a lot better. I could've been better with calls, getting them in and out of my mouth in and out of the huddle so they can get lined up and see the formation. To have some, it just felt like we were on our heels in those first four series of the game, especially when they're at home and they can dictate tempo with the way they're in and out of the huddle and their cadence system, which I think is one of the best in football. Good learning experience for everybody and hopefully we get to see them again."

You've talked a lot about time coverage with the pass rush, but when an offense is getting rid of the ball so quickly, sort of negating that pass rush, what needs to change from the secondary standpoint?

"From a secondary standpoint, it's just my opinion, you've got to get stickier. You've got to contest more football, you've got to contest more to give the D-Line a chance to get home. You've got to be great in your zone coverages and taking away those windows so the quarterback can hitch. When you play a rhythm quarterback like [New Orleans Saints QB] Drew Brees and like we're about to play here with [Atlanta Falcons QB] Matt Ryan, you've got to be very precise in your zone coverages. Your feet have to be in the ground, you have to be ready to go play football and you have to have a sense of urgency about you because that ball's coming out quick. If you're on it and you can get him to hitch, then you can bring the pass rush back to life. It starts in the back end where usually you talk about rush and coverage, you almost want to flip it and say coverage and rush, if I'm making sense."

If you're not going to have CB Richard Sherman or CB K'Waun Williams this week, how do you decide who's in the nickel and who's outside?

"We're working through that one. That'll present itself on Sunday."

We saw DL Kentavius Street in the summer and he was playing, it seemed like, mostly on the end. He's now inside. Is that an easy transition for him to make?

"With Street, I know he played some outside, especially when you're trying to get your feet wet, you'd love to just play a guy in the same spot over and over again. Ideally, he's probably more of an inside guy. Of course, rotation and injuries will always dictate where he plays, but we feel like he's got a chance to be a pretty good football player on the inside, whether it's at the nose or three-technique. Working to make sure he gets as much work at that as possible, but understanding that with the attrition that we've been having at the D-Line that we may have to flex him if he gets those opportunities."

Has that decision been made as far as who would step in for DL D.J. Jones or is DL Kevin Givens still, where does he stand in that whole mix?

"They're both working through it. So far, obviously, we have [DL] Sheldon [Day] who can supplement in there, [DL] Solomon's [Thomas] been doing a good job this year in there. They're both working through it and that decision hasn't been made. I think that's supposed to be made on Saturday."

When you're watching Street, we all know how powerful he is with the upper body. Do you just have to look at how his leg is mobility-wise?

"It's more confidence for him. I think his leg is stable and all that stuff and it's just the matter of him, like, when he's in drill work, you see all the explosion and all that stuff. For him, when he gets around bodies, to trust that everything's fine and to translate his drill work to the field, and it's kind of what we've been working on here since he's gotten back."

When you have Sunday, you won't have DL Dee Ford and Sherman and maybe S Jaquiski Tartt and Jones and the list goes on. Obviously, that's the way it goes, but do you have to say like, at some point, we're probably not going to be quite the same defense we have been?

"Talk to guys like [LB Dre] Greenlaw who stepped in for [LB Kwon] Alexander, or talk to [S] Marcell [Harris] who's stepping in for Tartt. They're starters in this league and that's the way they have to approach it. And so, the expectation is that there should be no drop off. We've got to coach them accordingly. And there's going to be a little rust. With Marcell, you saw in the first quarter a little bit of rust as a starter to come back in there. There's an adjustment. If you guys remember last year when he stepped in, he just progressed as the year went on, so the expectation for him and all those guys is that you keep working your tail off to get better every single day so there is no drop off. That's the mindset and like we've always said, the NFL doesn't really care about who's playing. The train's going to keep on moving."

How are you seeing DL Nick Bosa handling more snap load as the season's progressed, but also because of the defensive line attrition?

"He's been doing a good job with it. He's one of the more relentless human beings in terms of taking care of his body, all the regen stuff that they've got. He does a fantastic job with it. You'd like to limit his reps, obviously. We want to make sure that he's not taking too much of a load. A lot of things have been happening, especially over the second half of the season, where it's kind of forcing our hand. But he does, credit to him, he does a great job getting himself ready to play on Sunday so he can handle it."

Have you seen any downturn in his--?

"No teams just, I've never seen a rookie get more attention than he's gotten. The amount of chips he gets, the amount of double teams, I've never seen anything like it. I can't believe teams are afraid of a rookie, but that's their problem."

You can believe it, though.

"He is pretty good."

One more on Street. He is known for his weight room ability, but is that sort of overblown at this point? Does he need to work more on movement skills and things beyond just brute strength?

"If you watch his drill work, his drill work when he's out there in individual, he's probably the most impressive D-Lineman of the group, he really is. He is very powerful, all of it translates. Like I said, there's a confidence thing in there during OTAs and training camp and all that stuff where now there's bodies flying around, to trust that he's okay. He's been doing a really good job here in these couple of weeks and he's got to work through that mindset that he's freakier, he's stronger than most people, he's quicker than most people, he's more explosive than most people and he just has to trust that if he just delivers that every single play, play in and play out, that he'll be able to execute and perform at a high level."

What have you seen from defensive line coach Kris Kocurek both critiquing him and helping him get back up to that standard while also instilling him with confidence?

"Kocurek, I've always said, he's probably one of the best D-Line coaches in football if not the best D-Line coach in ball. He coaches every player with the same relentless passion and the same standard. There's no drop off, it doesn't matter. We had [LB Mark] Nzeocha take some D-End reps today to get through practice and he was coaching him like he would Nick Bosa, just yelling at him. But, that's the credit to Kocurek. It doesn't matter if you're on his D-Line or you're being asked to play a D-Line spot, you're going to have to execute and perform like one of his D-Linemen. Love him, he's doing a great job. I'm not worried about that transition."

On the first two-point conversion attempt, New Orleans Saints QB Taysom Hill ran into, you stopped him. The next day New Orleans Saints Head Coach Sean Payton said the safety just lined up on the wrong side of the ball as if it was kind of an accident or something. Was he in the right spot and did you guys sort of see that coming?

"We knew it was coming. I'm not going to say he wasn't on the right side because of the way we execute certain things and all our different goal line packages that we have, but that play was a gimme one to me with Taysom Hill where he was aligned. That was a layup in my opinion."