Kurtenbach: The 49ers and Brock Purdy are learning about life in the NFL

49ers 17, Vikings 22: Brock Purdy has been the Niners’ quarterback for a year. Now he and Kyle Shanahan have to face some real adversity.

And the 49ers, specifically head coach Kyle Shanahan and quarterback Brock Purdy, must adjust to living in this manner as well.

The Niners’ duo at the two most important positions in the game has had a lucky year since they joined forces a year ago this month.

Everything seemed to be going the Niners’ way until Purdy’s elbow exploded in the NFC Championship Game. Purdy’s recovery from the injury was also charming.

The pixie dust has vanished. Following a second straight loss on Monday to a 3-4 Vikings team in Minneapolis, capped by two Purdy interceptions in the final six minutes, this team is facing some genuine adversity.

“We were completely outmatched. “You have to take it like a man right now,” Shanahan said of the 22-17 loss.

The 49ers are up against the following: Deebo Samuel, a wide receiver, is out with a fracture in his left shoulder. Trent Williams, the team’s left tackle, was out with an ankle injury on Monday. Christian McCaffrey, the Vikings’ running back, was not at his best against them due to an oblique injury. And, most importantly, the Niners’ once-famous defense is in disarray. On Monday, Minnesota gained 452 yards. Injury cannot be blamed for the Niners’ poor record.

These may appear to be justifications for Monday’s defeat. They aren’t.

No, injuries and poor unit play are common issues in the NFL.

And these flaws make San Francisco look like every other team in the league.

That means the Niners will have to do what every other team does: rely on their head coach and quarterback to right the ship.

In the coming weeks, we’ll find out just how good Shanahan and Purdy are.

That’s because most of the league’s good teams rely on their quarterback — who is paid far more than anyone else — and a small group of other star players scattered throughout the roster to stay under the salary cap.

Those quarterbacks must do more with less, whether it’s random weapons, a deficient offensive line, or a defense that can’t keep them in games.

Typical quarterbacks do not have five All-Pro-caliber players surrounding them like Purdy (Williams, Samuel, McCaffrey, George Kittle, and Brandon Aiyuk). No, they’re fortunate to get two. Perhaps a great quarterback can make one more.

But there are no excuses. The best make the most of what they have, winning MVP awards and competing for Super Bowls. Others do not, and their teams either end up in NFL limbo or lose their jobs.

Where will Purdy fall now that the playing field has been leveled?

The Niners have never been asked this question before because Purdy is the NFL’s cheapest starting quarterback, earning less than $1 million per season. Combine his strong play (let’s not pretend he’s a scrub) with that low salary, and you’ve got a positive feedback loop. The Niners are committed to Purdy in the long run, but while he’s cheap, they’ll surround him with the best roster money can buy — the kind of roster that helped the team start 5-0 and look invincible.

Clearly, the Niners are not invincible because football is still a cruel, violent game in which injuries are all too common.

That is why quarterbacks, as well as head coaches, are paid so well in this league.

Good teams are most stable in these two roles.

If the quarterback-head coach combination is truly elite, it doesn’t matter who else is on the coaching staff or on the roster — the team wins.

While neither of the Niners’ losses can be blamed entirely on Purdy or Shanahan, the truth is that the bar should be set higher.

Both need to step up their game. That means not turning the ball over as much as he did in Cleveland and Minnesota.

For Shanahan, it means breaking out the deep cuts of the playbook — the Niners’ offense can be predictable and bland without Samuel — and possibly assisting with the team’s defense as well. (What an idea for a head coach!)

The Niners have a short week before facing the Bengals at home on Sunday, who have won two straight and are coming off a bye week. Samuel will be absent from the game. Williams is also not guaranteed to play.

It’s just another difficult location for San Francisco.

It’s chaotic, mentally and physically taxing. How do other teams function in the midst of this chaos?

It makes no difference; it’s the Niners’ lot now.

Let’s see if the team’s two most important members can help them out.