The Green Bay Packers still possess one of the NFL's most prolific offenses, but an improving defense has the squad feeling particularly good about its best start in four years.
Following breakout performances by Todd Gurley and Tavon Austin, the St. Louis Rams feel they're making similar strides on the other side of the ball.
As the Packers go after their 12th consecutive home win, the inconsistent Rams will try to remove a team from the unbeaten ranks for the second straight week Sunday.
Aaron Rodgers leads the league with 11 touchdowns passes and a 125.9 passer rating while leading Green Bay to the NFL's sixth-best scoring average at 28.3 per game.
The reigning MVP has no interceptions this year and none in 574 attempts compared to 48 TDs over his last 19 games at Lambeau Field, including three playoff contests. His last interception at home came against Minnesota on Dec. 2, 2012.
The Packers (4-0), however, may be most pleased with how they're playing defensively after holding an opponent to three points or less for only the second time since the 2011 season. They limited San Francisco to 196 total yards in last Sunday's 17-3 road win.
"They always say defenses win championships. As long as we're all playing on all cylinders, we can't be beat," said linebacker Nick Perry, who had two of Green Bay's six sacks.
That defense has held Kansas City and the 49ers to a combined 152 yards on 4.1 per carry in the last two games, including 20 yards on nine attempts by San Francisco running backs. Green Bay shares the NFC lead in points allowed (17.8 per game) and ranks eighth in the NFL in total defense (312.0 ypg).
The Packers now seek their first 5-0 start since winning their first 13 games in 2011. They've won all 11 home games since the beginning of last season, including a playoff matchup with Dallas, while averaging 37.2 points.
The Rams have been one of the most difficult teams to figure out, beating defending NFC champion Seattle in overtime in Week 1 and upsetting undefeated Arizona 24-22 on the road last Sunday. In between, they lost 24-10 at Washington and 12-6 to visiting Pittsburgh.
"It just shows that we have talent and all we have to do is come out and play every week and stay together as a team," cornerback Janoris Jenkins said.
St. Louis (2-2) was ranked last offensively after totaling 16 points and 471 total yards in its two defeats, but the squad is more optimistic after scoring three TDs against an Arizona team which allowed just four during its 3-0 start. The Rams racked up a season-high 164 yards on the ground against the defensively stout Cardinals.
Playing in only his second game because of a knee injury, Gurley displayed the potential that made him the 10th overall pick in this year's draft by running for 144 yards on 15 carries in the second half. The Rams didn't top 80 yards rushing in any of their first three games.
"(Gurley's) done all of the extra things. He's that complete back," coach Jeff Fisher told the team's official website. "That's the reason we drafted him, because we knew he was like that. ... He's a real pro."
Austin, the eighth overall pick in 2013, had six catches for 96 yards and two touchdowns after totaling eight receptions for 42 yards in the first three games. He also ran twice for 20 yards, improving his average to 7.7 per carry on 10 attempts.
Maybe the diminutive Austin could become a go-to guy for Nick Foles and a Rams team which has no one among the league's top 60 in receptions. Foles had three TD passes last Sunday after totaling two through his first three games as a Ram, finishing 16 of 24 for 171 yards without an interception.
"He plays within rhythm, he has good footwork, he's decisive, he knows where to go with the football," Packers coach Mike McCarthy told his team's official website. "It looks like he does a good job of scheme recognition pre-snap, and he does a good job running their system."
The man who runs things defensively, though, will be missing. Linebacker Alec Ogletree, who has a team-high 55 tackles, underwent surgery to repair his fractured right fibula on Tuesday.
The Rams are moving Akeem Ayers from strong-side to weak-side linebacker and have signed veteran Jo-Lonn Dunbar, who started for them at strong-side the past three seasons but was released at the end of the preseason.
St. Louis is tied with Green Bay for second in the NFL with 17 sacks, though the Rams have been susceptible against the run. They rank 26th at 120.3 yards allowed per game.
That's an area of concern against a Packers team that ranks third in the NFL with 136.3 rushing yards per game. Eddie Lacy is coming off a season-high 90-yard effort.
Wide receiver Davante Adams is almost certain to miss a second straight game due to an ankle injury, while a calf injury is likely to keep safety Morgan Burnett out again.
Green Bay has won four straight against the Rams, but the most recent came in 2012.