Led by first-year coordinator Jeff Ulbrich, Atlanta allows a league-low 253.4 yards per game and its 14 sacks are almost halfway to last season’s total of 31, which ranked worst in the NFC.

Last time out, the Falcons held 2024 MVP Josh Allen to 180 passing yards while intercepting him twice and sacking him four times in a 24-14 win Monday night. Atlanta doesn’t know if it will face Mac Jones or Brock Purdy at quarterback this week, but with Christian McCaffrey in the San Francisco backfield, head coach Raheem Morris knows his defense will have to continue to play at a high level.

“You know you’ve got to be ready for a tough, downhill run game,” Morris said of the 49ers. “I know it hasn’t been going up to this point for those guys, but we know how quickly that can change. They’ve been doing a great job being efficient in their pass game; they have two quarterbacks that have played well this year. … They’ve got a lot of really good football players, starting with Christian McCaffrey, obviously the most used player in football.”

Learning to play complementary football, Atlanta also boasts the leader in yards from scrimmage in running back Bijan Robinson, whose 822 total yards (484 rushing, 338 receiving) sit atop the NFL despite him playing in just five games. The next 11 players on the list — including McCaffrey (780 yards) — have played in six games.

Robinson, who was named NFC Offensive Player of the Week after piling up 238 yards from scrimmage against the Bills, appreciates the momentous run he’s been on, but realizes the team is only as good as its next win.

“We’ve got to put (the win over Buffalo) to the side super fast, because the 49ers just came off of a loss and that’s a great team,” Robinson said. “They’re going to come in ready this week, so that should be the focus at hand. As soon as we start getting into the praise from social media, then our focus is off.”

Prior to the 49ers’ 30-19 loss to the Tampa Bay Buccaneers on Sunday, each of their first five games were decided by five points or fewer. San Francisco (4-2) had its good fortune halted in Week 6, as it lost its leading tackler Fred Warner to a season-ending dislocated and fractured ankle. Compiled with five-time Pro Bowl defensive end Nick Bosa’s torn ACL, the 49ers’ defense could be reeling against a confident Atlanta team.

“Everyone knows how special Fred is to this team, both as a player and a person,” said San Francisco head coach Kyle Shanahan, who also gave an update on both injured quarterbacks. “Brock is more limited than Mac.”

As injury-marred as the 49ers’ defense is, the offense could see the return of several game changers. Veteran tight end George Kittle is expected to suit up for the first time since sustaining a hamstring injury in the season-opener against the Seattle Seahawks. Kittle was limited in his first practice back Wednesday.

At quarterback, Jones has filled in admirably for the injured Purdy (toe), throwing for 1,252 yards and six touchdowns in four games, but has been hampered with both knee and oblique injuries. Both players were limited participants Wednesday.

No matter the starter for Shanahan behind center, he knows the offense will have its hands full with the upstart Atlanta defense.

“I see a bunch of good guys. They’re all very active,” Shanahan said of the Falcons defense. “Every one of them has the ability to rush the quarterback. I think their scheme and how they’re coached is very good. They’re playing the right way and they’re talented.”