"You can't take these guys for granted."

Deebo Samuel's words on the Friday before the 49ers' Week 4 clash with the Cardinals articulated the prevailing sentiment in the San Francisco locker room going into the meeting with an upstart Arizona team.

And, having seen the Cardinals upset a previously undefeated Cowboys team a week earlier, the 49ers made it clear right off the bat on Sunday that they were in no mood to take their opponents lightly and risk a similar outcome that would spoil their own undefeated start to the season.

Fewer than 16 minutes into the game, the 49ers were up 14-0. The Cardinals had either taken the lead or hung around during their first three games, the 49ers never allowed that to happen.

For as spectacular as the second of Christian McCaffrey's four touchdowns was, the running back delivering a highlight reel hurdle en route to the endzone, what was most striking about the 49ers' dominance was how unspectacular they made it seem.

Brock Purdy hit two deep balls to Brandon Aiyuk, the first being one on which the wideout demonstrated superb ball-tracking, but there was otherwise little that seemed overly special about a performance that saw Purdy break the 49ers' record for single-game completion percentage, going 20 of 21 for 283 yards and a completion percentage of 95.2.

That is not a knock on Purdy, who, per NextGen Stats, had a completion percentage over expectation (CPOE) of 28, the highest mark by a quarterback with a minimum of 20 attempts over the last seven plus seasons. To the contrary, that it felt routine is a reflection of how easy he and the 49er offense are making things look.

It wasn't all straightforward for San Francisco. Arizona did, to its credit, fight back and cut a 21-3 deficit to 21-16, giving a defense that got plenty of push up front but surprisingly struggled to bring down Cardinals quarterback Joshua Dobbs, plenty to work on going into a mammoth Week 5 matchup with the Cowboys on Sunday Night Football.

But the 49ers' riposte the Cardinals' show of spirit was telling. An eight-play, 75-yard drive, capped by McCaffrey's fourth score. Comeback over.

Essentially, this game followed the pattern of the last three weeks for the 49ers. After dominating the Steelers in Week 1, the Niners have had more than enough in the tank to hold off their opponents and have won comfortably without having to perform at anywhere close to their highest level, and that is why it's difficult to view them as anything other than the best team in football through four weeks.

That status will receive its sternest challenge yet in primetime next week. However, just as they were prepared for a feisty Cardinals team, you can bet the 49ers will be ready for a fascinating matchup with a team they could well face in the NFC Championship Game this season.

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