49ers' unexpected loss to Cardinals shows challenges of defending NFC West title

The 49ers are in for another grueling divisionbattle this year, and the difficulty oftheir title defense was on full display Sunday afternoon in a 24-20 lossto the team expected to finish last in the NFC West.

Kyler Murray led back-to-back electric, go-ahead drives for the Cardinals in the fourth quarter to beatSan Francisco's much-hyped defense. He did it with his legs, capping a 14-playdrive with a score on the ground, and with his arm, completing five straight passes to set up an easy run from the 1 for teammate Kenyan Drake. He worked out immediatechemistry with newcomer DeAndre Hopkins, who finished the contest with 14 catches for 151 yards in his debut.

San Francisco, which reached the Super Bowl in February, came into Week 1as a 5.5-point favorite over the Cardinals. By overcoming those oddsat Levi's Stadium, Arizona showed itcouldbe a disruptorin 2020 behind itsfast-developing offense and a defense that has nowhere to go but up following its putrid play a season ago. The Seahawks and Rams are expected to be strong division contenders, too.

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It remains to be seen whether the 49ers will avoid regression in the areas they leaned on most for success last year. They traded standout defensive tackle DeForest Buckner to the Colts and running back Matt Breida to the Dolphins during the offseason. They set a high standard in 2019 that will be difficult to replicate. If they don't have the best defensive unit in the league or a dominant run scheme, pressure will increase on quarterback Jimmy Garoppolo to carry a greater load.

San Francisco's defensive line and running game produced mixed results against the Cardinals.

Murray repeatedly broke containment and paced Arizona with 91rushing yards. As a team, theCardinals ran for 180yards — more than any team racked up in a single contest against San Francisco last season. The 49ers' ground attack, meanwhile, managed 123 yards and at times struggled to move the ball.

Given the talent San Francisco still has in its defensive front and depth it possesses in its backfield, the club expects to roar back next week at the Jets.

But the 49ers face a challenge unlike any conference rivals from other divisions are taking on. The NFC South will likely be able to beat up on the lowly Panthers, and the NFC North and NFC East project as uninspiring containersof mediocrity. There are no cupcakes in theNFC West.

The Cardinals on Sunday looked like a .500 team or better. Expect them to be agents of chaos in a division San Francisco needs to win to gain home field advantage in the playoffs.