Brock Purdy and the 49ers prepare for a tough test against the Broncos defense

SANTA CLARA, Calif. (AP) — Brock Purdy and the San Francisco 49ers have been in peak form early this season.

The Niners lead the league in yards per play and success rate, have limited negative plays and rank second in the league in scoring to fuel a 3-0 start. That unit will get its toughest test yet on Sunday when the 49ers host the Denver Broncos (2-1) and one of the league's best defenses under coordinator Vance Joseph.

“Vance is one of the toughest guys just because he can do anything,” San Francisco coach Kyle Shanahan said. "It’s not a surprise they were one of the best defenses in the league last year.”

But no offense is operating like the 49ers early this season with the team averaging 32.7 points per game and scoring touchdowns on nearly half of their possessions.

While the big plays such as the 82-yard hook-and-ladder touchdown last week against Arizona get the highlights, the key has been avoiding negative plays.

The offense has gone 11 straight quarters without a turnover and has lost yardage on just four plays from scrimmage all season — the fewest through three games since at least 2000.

The 49ers are the first team in 12 years to allow no sacks through three games as Purdy's elusiveness and strong play from the offense line have frustrated the opposition.

“Obviously, the play calling, the boys up front, the receivers being on top of making sure they’re running the right routes and getting the ball out on time and stuff on our end at quarterback. So, it’s a unit thing,” Purdy said about the lack of sacks. “It takes everybody. Obviously it starts with the boys up front too, though. They’re playing their butt off right now.”

The Broncos offer a formidable challenge. They lead the NFL with 139 sacks since the start of the 2024 season — 27 more than the next best team — and know they need to get pressure on Purdy to have a chance Sunday.

That's not as easy as it sounds.

“He’s playing at a real high level, very decisive," coach Sean Payton said. "He’s through his progressions fast. Kyle and those guys have done a great job, whether he’s under center or in the gun. The mix of run, play pass and drop back is impressive. You see in three weeks, not only no sacks, first in third down, first in red zone, very efficient. He’s making all the throws.”

Denver (2-1) vs San Francisco (3-0).

When/where to watch: Sunday, 4:25 p.m. EDT, CBS.

Latest odds: 49ers by 2 1/2.

Against the spread: Broncos 2-1; 49ers 2-1.

Last week: Broncos beat the Rams 30-26; 49ers beat the Cardinals 36-30.

Last meeting: Broncos beat 49ers 11-10 on Sept. 25, 2022, in Denver.

Series record: Tied 8-8.

Broncos run defense vs. 49ers run game. San Francisco is off to a strong start running the ball this season, ranking fourth in the league with an average of 5.1 yards per carry, up from the 30th-ranked 3.8 last season. Stopping the run has been an issue early this season for Denver. The Broncos allowed 220 yards rushing in a season-opening loss to Kansas City and rank 30th with 5.1 yards per carry allowed.

— The Broncos have won 10 straight nonconference games for the longest active streak in the NFL.

— Denver QB Bo Nix has had 10 fourth-quarter comebacks since being drafted in 2024 for the most in the league in that span.

— Broncos S Talanoa Hufanga will face the 49ers for the first time since leaving in free agency last year. Hufanga had one sack and two interceptions, including a 66-yard return for a TD last week.

— Denver ranks second to last in the NFL with 81 yards rushing per game and third worst by allowing 143.7 yards rushing per game.

— The 49ers look to start 4-0 for the fifth time in the Super Bowl era. They made the Super Bowl three of the four times, including in 2019 and 2023 under coach Kyle Shanahan. Shanahan will coach his 167th game in the regular season or playoffs with the Niners, breaking the record held by Bill Walsh.

— San Francisco has scored touchdowns on 48.2% of offensive possessions this season for the highest rate through three games since at least 2000. The previous high was 47.2% for Miami in 2023.

— The 49ers have allowed only four plays from scrimmage of at least 20 yards, tied for the second fewest in the NFL.

— Purdy's 10 total touchdowns passing and rushing are tied with Steve Young (1998) and Frankie Albert (1948) for the most through three games in San Francisco history.

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