GREEN BAY, Wis. (AP) The unbeaten Green Bay Packers have some news for their upcoming opponents.
''I just think we're scratching the surface a little bit,'' quarterback Aaron Rodgers said after the team improved to 3-0 for the first time since 2011 with a 38-28 victory over the Kansas City Chiefs on Monday night.
Packers coach Mike McCarthy has mentioned the importance of getting off to a fast start this season, and a victory at San Francisco on Sunday would mean the 4-0 first-quarter record McCarthy envisioned.
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But what has McCarthy most excited is how he sees so much room for improvement on both sides of the ball.
''I think we're doing a lot more good things than we are (bad things),'' McCarthy said Tuesday. ''Obviously (there are) corrections that need to be made.''
The Packers sacked the Chiefs' Alex Smith seven times on Monday night. And at the time of the fourth of Rodgers' five touchdown passes, the Packers had a 31-7 lead and the defense had held Kansas City to 88 total yards midway through the third quarter.
Playing with a 24-point lead, the Packers surrendered 238 of the Chiefs' 326 total yards and a pair of touchdowns that made the final result look closer.
After allowing Chicago's Matt Forte to rush for 141 yards on 24 carries in the Sept. 13 opener, the Packers have contained two of the league's top running backs - Seattle's Marshawn Lynch (15 carries, 41 yards) and Kansas City's Jamaal Charles (11 carries, 49 yards).
''We obviously have high expectations for our defense and what we like to do,'' said linebacker Clay Matthews, who had his first two sacks of the season on Monday night.
''Obviously I think for the most part of three quarters we kept that up, but obviously (there was) a little letdown in the fourth quarter. We'll adjust that and correct that. Anytime the offense is able to put up that many points, it allows you to play a little more freely and a little more loose, and get after the quarterback and create those big plays.''
Asked Tuesday if he was concerned about the yards - and 16 points - his defense allowed in the fourth quarter, McCarthy said that execution was an issue, even if defensive coordinator Dom Capers was taking a less aggressive approach with a big lead.
''We were in this situation a number of times last year,'' McCarthy said of his team building big leads at home last season.
''You have to grade the tape the same all the way through, regardless of the scoreboard. That's the only way you have a chance to grow. It's about making a call and everybody executing the call, being on the same page.''
Even the offense, which has been efficient in the first three games, has room for improvement - although Rodgers appears to be at the peak of his ability. He leads the NFL in passer rating (135.4) and touchdown passes (10).
Rodgers, New England's Tom Brady and the New York Giants' Eli Manning are the only three starting quarterbacks who haven't thrown an interception this season.
''There's corrections to be made all over the place. We're leaving a lot of plays out there,'' said wide receiver Randall Cobb, who caught three of Rodgers' five touchdown passes against the Chiefs. ''It's a good place to be in, but you can't slow down. You can't get too comfortable. You have to make sure that you continue to prepare each week and get ready for your next opponent.''
That next opponent is the 49ers, who are off to a rocky start under first-year head coach Jim Tomsula. But they have won four straight against the Packers going back to the start of the 2012 season.
The 49ers knocked Green Bay out of the playoffs following the 2012 and 2013 seasons. In the first matchup, quarterback Colin Kaepernick punished the Green Bay defense by rushing for an NFL quarterback playoff record 181 yards and the Packers allowed a franchise playoff record 579 total yards.
''Hopefully, this is just an indication of where we're headed as a defense,'' Matthews said of the team's fast start. ''As we talked a lot last year coming off that (NFC Championship game) loss, we felt like we had a good thing going on defense.
''It's about tapping back into that and carrying that thing over into this year. Here we are at 3-0, and for the most part, we've held three very good offenses in check.''
NOTES: McCarthy did not have an update on wide receiver Davante Adams, who aggravated his left ankle injury during the opening series and did not finish the game. . McCarthy said that tight end Andrew Quarless, who left the game with a knee injury, will not play against the 49ers. ''I don't think he will make it this week,'' McCarthy said.
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