If you doubted the San Francisco 49ers before, you probably don't now.

Sunday's victory by the still-undefeated Niners was impressive, but much of the credit has to go to coordinator Robert Saleh's defense, which held one of the highest-scoring offenses in the league to just seven points, and those came on the Rams' first drive of the game.

The defense took that run-focused drive personally.

The 49ers went on to score 20 unanswered points and the defense, embarrassed by that initial effort, didn't let the Rams do much else for the remainder of the game.

"They decided to run it nine straight times," defensive tackle DeForest Buckner said after the game. "That definitely hits you on a personal level, especially because we've been playing really good run defense (the 49ers had not allowed a rushing touchdown until that drive). We know they're a really good run team, and that's what they thrive on. They go from the run, the play-action pass, and they can drop-back pass.

"I'm pretty sure a lot of guys took it pretty personal. We even told each other, 'They ran it nine straight times.' As a man, you don't like to see that on the defensive side. It really sparked into that goal-line stand, for sure."

The 49ers remain one of just two undefeated NFL teams and are now 5-0, still alone atop the NFC West standings. Sunday's win will have many doubters take notice and re-evaluate what they thought about Kyle Shanahan's squad. The head coach was asked if the Niners should be considered an elite team now.

"No," Shanahan replied. "I'm not going to ever use that word."

Added Shanahan: "I'm very happy with how we played. We're 5-0, which is a great thing, but we're not playing our best ball. We can do a lot of things better than that. It seemed like our defense played at an extremely high level, obviously minus the first drive. We can continue to get better on offense. We can continue to get better on special teams. I also think our defense is just getting started, too."

So what are the next steps for this already impressive 49ers defense?

"I mean, the did score seven points," Shanahan (maybe somewhat) jokingly responded. "I mean, our defense is playing great. I've got a lot of confidence in them. You guys can see the pass rush, but the seven guys behind them are good players too."

Cornerback Richard Sherman doesn't view Sunday's defensive performance as anything out of the ordinary for this group of talented players.

"It's business as usual," he told reporters. "The previous performances should have been enough to get these guys the respect they deserve."

They'll likely get it now. The 49ers are 5-0 for the first time since 1990. Their next game will be another road matchup on October 20 against the Washington Redskins.