The 49ers had one of the best defenses in the NFL in 2019, and that unit was expected to be just as good this season.
But the Arizona Cardinals weren't intimidated by the vaunted 49ers' defense as they came into Santa Clara on Sunday and left Levi's Stadium with a stunning 24-20 win over the 49ers.
Dynamic quarterback Kyler Murray and top wide receiver DeAndre Hopkins led a potent Cardinals offensive attack that piled up 404 total yards Sunday.
"Once the offense got going, I knew it would be hard to stop us with a guy like Kyler Murray back there at quarterback, Kenyan Drake at running back and [Chase Edmonds], it's hard to stop this team once we get going," Hopkins told reporters after the game. "We practice the way we play. Fast tempo and everyone's in shape. We knew coming out, once we started clicking, it would be hard to stop us.
"We saw some things on film that we could take advantage of and you've got to give a lot of credit to [Cardinals coach Kliff Kingsbury] for calling it at the right moment, those big plays."
Last season, the 49ers allowed over 400 yards of total offense just once -- the thrilling 48-46 win over the New Orleans Saints in Week 14.
Now, the 49ers have started off the 2020 season by allowing 400-plus yards and the team that beat them says they saw a weakness in their defense while preparing for the season opener.
Murray threw for 230 yards and ran for 91, while Hopkins caught 14 passes for 151 yards. Those are totals the 49ers aren't used to giving up.
You can expect 49ers defensive coordinator Robert Saleh to patch up that hole this week as the team gets set to face the New York Jets in East Rutherford, NJ.