49ers ride dominant defense — and tone down offense.
It’s not just opposing quarterbacks and offensive coordinators: The 49ers’ defense is also having a profound impact on Jimmy Garoppolo and Kyle Shanahan.
That is, the defense has been so dominant that Garoppolo’s statistics and Shanahan’s aggressive instincts have been suppressed this season.
Shanahan acknowledged Monday it can be frustrating as a cut-it-loose playcaller to not get into a passinggame rhythm. And he’s not alone. Garoppolo, who has gunslinging tendencies, has been asked to be a caretaker instead of a risktaker: He’s overseeing an offense ranked 30th in the NFL in pass attempts per game (29.4).
“Sometimes it can be tough for a quarterback when we’re managing the game a lot with our defense — when they get us to some leads and with the way they’re playing,” Shanahan said. “There come times in certain games where you feel the only chance for the other team to win is if we turn it over. So you try to get in those situations where you want to eliminate the possibilities of that.”
To be clear, Shanahan and Garop
“It can be tough for a quarterback when we’re managing the game ... with our defense . ... I don’t think I’ve ever been on a team with a defense in the top 10.”
Coach Kyle Shanahan on winning with defense
polo haven’t been complaining.
The NFL’s secondranked defense is the biggest reason the 49ers (50) have already topped last year’s win total. The 49ers have allowed their fewest points (64) through five games since 1997. And they’ve surrendered their fewest points (10) in a twogame stretch since 2012 in recent romps over the Browns and Rams.
As a result, the 49ers have led for 125 minutes and 45 seconds of the 150 minutes they’ve played after halftime this season.
And that means their secondhalf strategy has involved taking the air out of the ball instead of airing it out. They have 118 rushing attempts and have thrown 55 passes after halftime.
Having a ferocious defense is foreign for Shanahan. He never had a defense ranked among the NFL’s top 12 in his previous 11 seasons as a head coach or offensive coordinator. In fact, those defenses ranked among the league’s bottom half for seven of those seasons.
The need to keep up with opponents is why Shanahan’s offenses have generally been passhappy: They ranked among the league’s top seven in pass attempts in seven of his previous 11 seasons.
(These are) “things that you’ve got to work on as a play caller, which are things I’m going through, and also as a quarterback,” Shanahan said. “I don’t think I’ve ever been on a team with a defense in the top 10.
“There’s a time and place. You are responsible for that ball and you’ve got the whole team counting on you. Sometimes we’re counting on you to give us a chance to win. And sometimes we’ve got to count on you to not give the other team a chance.”
The 49ers entered the season like most teams: They figured their chances would hinge on the performance of Garoppolo, whose erratic moments this summer were the dominant story line.
However, Garoppolo has taken a back seat to the defense and the 49ers’ secondranked rushing attack: Garoppolo ranks 19th in the NFL in passing yards per game (232.6), 16th in touchdown passes (7) and 14th in yards per completion (11.4).
Garoppolo’s generally solid performance has been marked by an occasional headscratching throw. He’s tossed five interceptions and has the NFL’s sixthhighest interception percentage (3.4).
On Sunday, he tossed an interception under pressure on thirdandgoal from the 1yard line, although Shanahan largely absolved him because he thought tight end George Kittle was being held in the end zone. Garoppolo also stared down wide receiver Dante Pettis on a slant and linebacker Cory Littleton stepped in front before dropping a probable picksix.
“Sometimes we’re counting on you to give us a chance to win. And sometimes we’ve got to count on you to not give the other team a chance.”
Coach Kyle Shanahan, on why QB Jimmy Garoppolo often lets the run game take precedence over passing aggressively — he doesn’t have to
In Week 1, against the Buccaneers, Garoppolo did throw an interception that was returned for a touchdown. In Week 2, against the Bengals, he threw an interception into quadruple coverage.
Asked about Garoppolo’s risktaking, Shanahan, admittedly impatient, noted he shares the gene. A prime example: In 2017, in his first game as a head coach, Shanahan went for it on fourth down twice in the first half, and both times it backfired.
Two years later, times have changed. And Shanahan’s approach is also being altered.
“I like a (quarterback) who naturally is (aggressive),” Shanahan said. “I’d like to say I’m naturally that way. I want a guy who’s not scared to make the big play and who’s going to put it more on his shoulders and not always try to play it safe. But you’ve also got to adjust to your team, too.”
Eric Branch is a San Francisco Chronicle staff writer. Email: ebranch@sfchronicle.com Twitter: @Eric_Branch