The San Francisco 49ers improved to 6-0 on the season with a 23-17 victory over the Washington Commanders on "Monday Night Football" at Levi's® Stadium.

After building a 20-point lead, San Francisco held off a late Washington comeback, with safety Malik Mustapha delivering two critical defensive stops to help secure the win.

Following the game, head coach Kyle Shanahan and several 49ers players reflected on the team's defensive performance, second-half struggles, and undefeated start.

Here's what they had to say:

Niners Liners

Shanahan on the team's ability to finish the game and remain undefeated:

"I just told them, I don't care how it ended in terms of some of the stuff that guys were frustrated about. I was just really proud that they found a way to persevere and get that win. Anytime you get off to such a good start and you have a comfortable lead and it slowly dwindles and the other team has the ball down less than one score inside the 50, it's not a good feeling... I thought that was a huge challenge for our guys to just the competitive stamina to keep that focus, to keep it going, to not think negatively of the fact that we let them back in it. I was just proud of them for being able to finish it and find a way to get a win."

Shanahan on the team's 6-0 start:

"I feel good that we just won a game. I mean, 6-0 is better than any other options in your record, but definitely, I feel good when the year's over and you're the last team to win the last game of the year. So, I'll wait until that moment."

Shanahan on the offense's second-half:

"It's definitely a big deal when you lose a player like WR Mike Evans, but our first drive I thought was one of our better drives of the game. We ran the ball real well, we just got a ball tipped on third down that would have been a score and we got a field goal. The next two drives really, we got a sack on first down, got us into second-and-20. We went three-and-out both times and then the fourth time was a four-minute drill. We were trying to run the clock out. So just the way it ended up being, Mike wouldn't have had a chance to have much of an effect there in the second half."

Shanahan on DL Mykel Williams recording his first sack since returning from injury:

"It's huge... I'll see how the tape looks, but just for him to string two games in a row, get him back from a bad injury. It's been a long recovery for him and I'm just really happy that he's made it back. Been out there two games and hopefully didn't have any setbacks in this game and can keep getting better with another week of practice."

Shanahan on DL Romello Height's impact on the defense:

"It seemed like he was all over the place. I thought he made a number of plays. It looked like he got a couple sacks, I don't know if they got taken back or not. I'm not sure of the stats from the game, but with what I saw out there, he looked like he had a big impact."

Shanahan on the decision to go for it on fourth-and-three in the red zone:

"It was just a gut feeling. Just the way the game was going I thought we were going to get it. I thought we had a real good chance to get the play right before it. I was frustrated we didn't. It's something we don't always do, but it just felt right there and it worked out."

49ers Players

S Malik Mustapha on his fourth-down pass breakup to help seal the win:

"We are just in man coverage. I'm just reading the stem of the receiver and then he broke out and I was just trying to race to the pylon. Then, once we got to the catch point, I just wanted to be physical at the point of attack and get that ball out."

Mustapha on making consecutive defensive stops in the 4th quarter:

"On third down, you get the stop because, it's four down territory. I was like, 'alright, we got to get off the field again.' It's just rinse and repeat, rinse and repeat. You can't be dwelling on one play, whether the outcome is good or bad. We just got to be on to the next. Even when I got the fourth-down stop, yeah, we're celebrating. At the end of the day, there's a sense of urgency that we're going to be able to have to go on the field again."

LB Fred Warner on Mustapha's two late defensive stops:

"He's unbelievable. Unbelievable. That play he had where he ran up and stuck that dude in the hole in the run at the end, then that play he had to get us off the field in coverage – he's a fantastic player and I'm happy he's on our side."

T Trent Williams on Mustapha's physicality and game-changing plays:

"He's an enforcer. We need guys like that. Not only that, you see what he does for us in the pass game. Literally won the game for us in the corner. At the pylon, breaking up that pass. He had a major breakup last game, he got him out of bounds. He's doing it all. So yeah, I think the missile really describes him well, but it doesn't really encapsulate everything he does for this team."

QB Brock Purdy on the defense stepping up to secure the win:

"Obviously offensively and for myself, in the second half, it's tough just to do what we did, three-and-outs... But, for our defense to do what they did, obviously I know it sounds cheesy, but I mean it's true, it's a team win. It takes a whole team collectively for four quarters. And so, for our defense to do what they did at the end, that was really impressive."

Purdy on the team's second half:

"Yeah. Obviously, just with the lead that we had, it's like put your foot on the gas pedal and go make plays and put the game away kind of thing... But, at the same time, it's the NFL. Every single Sunday, today Monday, it's a competitive game. You've got the best players in the world in the sport playing and you just never know what can happen."

TE George Kittle on Mustapha's energy and impact on the defense:

"I know that Malik was like gnawing on a bone like a rabid dog when he wasn't playing and so the fact that he's getting in there and now he's just taking advantage of that opportunity... That juice that he brings, I know that that helps (LB) Fred (Warner), that helps the defense, keeps his guys alive. And that play in the fourth quarter where he just came down and stuffed the running back, that was fantastic."

RB Christian McCaffrey on the young defensive linemen stepping up:

"It's so cool. When you go through training camp, there's always guys that you're excited about and dudes that you have your eye on. 'Hey, I think that guy can play,' but you never know until the game starts happening. Those guys have not just proven us right, but they've upped the standard and upped the bar of what I thought they could do. It's been so cool to see them step into their role with elite energy, confidence, and playing great football for us."

Washington Commanders

Commanders head coach Dan Quinn on Washington's second-half comeback:

"I loved the way we ended the third quarter and most of the fourth. I think our team demonstrated that these guys are built for tough spots and moments. But the first half was rough. To have third downs go poorly on both sides of the ball. I thought those were going to be one of the real keys to the game."

Quinn on the 49ers defense making critical stops:

"They had come on there and had made some third downs. So for us, getting some stops, getting it back, but 23 - it felt worse than that, honestly. San Francisco is already a tough team and we spent way too much time in the first half battling ourselves."

Quinn on Washington's failed fourth-down conversion late in the game:

"No, I definitely knew it was fourth down. We were going for it. I was probably saying, like with the illegal shift, there's not a penalty to go for a field goal. I think somebody had asked me, 'can we kick a field goal?' So no, we were going for it. We knew we had to go for some fourth downs to be bold in the game."

Commanders QB Jayden Daniels on Washington's second-half adjustments:

"We just started taking it one play at a time. Limiting the errors, the pre-snap penalties and post-snap penalties that were keeping us back behind the sticks, and we started going one play at a time."

Commanders LB Frankie Luvu on Washington's adjusting defensive performance:

"Just adjusting off what they were doing. You know, it was a lot of in-cuts and deeper routes. So getting us in the call, and I felt like a good job of DJ [Washington Commanders defensive coordinator Daronte Jones] giving us a call to be in the best position. And just taking every high-low as you can and balls going back to the check point. And also caging the pocket for explosive runs."

Commanders S Jeremy Reaves on Washington's resilience:

"You've got to stay together, man. It's a long season. We lost some fallen soldiers, but you've got to keep going. At the end of the day, we've all got a job to do despite the circumstances, right? We're still expected to show up and you have to show up. We still have a lot of ball left. We've still got to figure it out."