The Game Plan and Final-Score Prediction for the 49ers against the Cardinals

Here are the five things the 49ers must do to beat Arizona on Sunday.

The 49ers should beat the Cardinals on Sunday.

Should.

That doesn’t mean they will beat the Cardinals. Arizona is an up-and-coming team with a phenomenally talented quarterback, Kyler Murray, and a three-time All Pro wide receiver -- DeAndre Hopkins.

Plus, this game won’t be a typical game, because the preseason didn’t happen. In a sense, this is the first week of the preseason. Neither team has reached the dress-rehearsal level, so neither team is particularly prepared to play. Whichever coaching staff manages these unusual conditions best will win.

Here are the five things the 49ers must do to beat Arizona on Sunday.

1. Keep it simple on offense.

Kyle Shanahan likes to confuse the opposing defense before the play with a million shifts and motions. Because each time a player on offense shifts, the defense has to shift as well and each defender’s responsibility changes. And if one of 11 defenders doesn’t shift correctly, he’ll be in the wrong place during the play and will create a huge hole for the 49ers offense.

Shanahan’s complex offense works. But Week 1 after no preseason, all those shifts and motions could confuse his own players and lead to lots of false starts, illegal shifts and procedural penalties. Meaning they could beat themselves with avoidable mistakes.

The 49ers don’t have to trick or outsmart the Cardinals to beat them. Shanahan can call six basic run plays and 12 basic pass plays with minimal shifts and motions and the 49ers’ talent and experience can carry them to victory.

2. Don’t throw the ball to Dante Pettis in traffic.

Bad things happen when Jimmy Garoppolo throws to Pettis. Usually interceptions happen.

Pettis might have to start if rookie Brandon Aiyuk doesn’t play -- Aiyuk has a strained hamstring. But even if Pettis starts, the 49ers shouldn’t force him the ball -- one interception could lose the game for them. Let Garoppolo throw to George Kittle, Jordan Reed, Kendrick Bourne, Kyle Juszczyk, Trent Taylor, Ross Dwelley, Raheem Mostert and Jerick McKinnon instead. The 49ers have plenty of options who are much more reliable than Pettis.

If Garoppolo commits zero turnovers, the 49ers almost certainly will beat the Cardinals.

3. Substitute players on offense and defense as much as possible.

Especially the players who missed time during training camp -- Nick Bosa, Dee Ford, Fred Warner, Brandon Aiyuk. None of them should play 60 snaps on Sunday.

The 49ers should use their depth and rotate players as much as possible. Otherwise, they’ll get to the fourth quarter and find they’re exhausted. And the Cardinals will try to tire out the 49ers defense by using a no-huddle offense, which will prevent the 49ers from substituting between plays. Meaning the 49ers might have to use timeouts mid-drive on defense.

The 49ers also should rotate wide receivers and running backs every couple plays on offense. None of the 49ers skill players should stay on the field for a full 12-play drive. They’re not in good enough shape. The 49ers should be as conservative as possible. They don’t need to score lots of points to win this game.

4. Play Raheem Mostert on special teams.

He’s the starting running back now, but he’s also an elite special teams player. And one way the Cardinals could pull off an upset is by returning a punt or kickoff for a touchdown. The 49ers haven’t done live tackling on special teams all offseason -- no team has. So the Niners might give up a long return. Mostert will reduce the chances of that happening.

5. Wear out Cardinals right tackle Kelvin Beachum.

Beachum was supposed to be the Cardinals’ backup right tackle. But the starter, Marcus Gilbert, opted out. So Beachum takes his place. The Cardinals are paying him less than $1 million this season.

He’ll have to take turns blocking Arik Armstead, Dee Ford and Nick Bosa. Good luck. And on third downs, the 49ers probably will blitz right at him. And he will give up lots of pressure, and Kyler Murray will go down.

And the 49ers will win a close, low-scoring game by a score of 17-13. Or they should win 17-13, if they follow this simple game plan.