The most important part of the Chiefs’ offense that the 49ers’ defense must stop

Steve Wilks can help out his players by adjusting. The question is: Will he?

The stage is set for San Francisco 49ers wide receiver Deebo Samuel to have a monster game against the Kansas City Chiefs and a defense that struggles to defend No. 2 wide receivers.

Let’s switch gears and talk about one facet when the Niners are on defense. Steve Wilks called Patrick Mahomes “the best I’ve ever seen for just buying time, winning with his feet, and getting the ball where it needs to go down the field.”

Any Mahomes superlative is justified. But the discussion about this side of the ball has been simplified to the quarterback, a poor Niners run defense, and that’ll equal points for the Chiefs.

The Niners indeed struggled to stop the run, as they were 25th in EPA per rush allowed. But assuming that the Chiefs will carve San Francisco up is misinformed. The Chiefs are not a team that generates big plays on the ground, as evidenced by their 21st ranking in EPA per rush.

So, we have the immovable force going against the moveable object. As long as Mahomes is under center, the Chiefs will be a threat through the air. But this defense makes you earn everything. San Francisco was fifth in the NFL in EPA allowed per pass. They were also fifth in limiting yards after the catch.

There aren’t many areas on the field where the Chiefs excel through the air. They know their personnel and don’t test teams often beyond ten yards. Of the 12 field zones over ten air yards, Kansas City is only proficient in two, and one of those happens to be right down the middle at ten yards, where Fred Warner patrols.

Stopping the screen game

There’s one area where an Andy Reid offense always seems to excel, and it’s in the screen game. Save a Mahomes miracle play; stopping the Chiefs’ screen game should be priority No. 1 for Wilks and the 49ers’ defense.

In a year where many critics went out of their way to shame Brock Purdy, Mahomes led the NFL in percentage of passes that were screens at 15.7 percent. They were effective at it, as they generated the third-highest EPA on screen passes in 2023.

Rashee Rice was 18.4 percent of the Chiefs’ target share, three percent below Travis Kelce but ten percent higher than the next wideout on the team. His most-targeted route? You guessed it, a screen.

Nearly a quarter of Rice’s targets were at or behind the line of scrimmage. Rice led the league in total yards after the catch because of this. The 49ers must be ready to tackle Rice, as he forced 16 missed tackles during the season. Rice had a 60 percent success rate on 30 targets on screen passes alone.

It would behoove Wilks and the Niners to place in the face of the Chiefs wideouts, specifically Rice. If not, you’re opening the door for free yards, like the Philadelphia Eagles did below:

He had a 33-yard touchdown nullified last week on a screen pass due to an offensive holding penalty.

It’s an easy way to manufacture yards when you have a quarterback who is as accurate and on time with the ball as Mahomes. The Niners will have their hands full with Kelce and Rice if they elect to play soft coverage — especially in the low red zone.

Will Wilks change it up?

Going back to Week 10, the Jacksonville Jaguars saw something from San Francisco’s defense that made them lean heavily into screen passes. Since then, we have seen every team dedicate at least a drive to quick throws behind the line of scrimmage.

You slow down the pass rush and force the 49ers secondary to make a tackle. They were hit or miss in this department, as the Niners finished the season 15th in EPA per pass allowed against screens.

Tackling has been an issue through two playoff games, as the 49ers have missed nine tackles in each game. Forty-seven percent of the Packers’ yards came after the catch — but the bulk of that was due to slipping. However, there were no excuses for the 46 percent of yards after the catch against the Lions.

This has to be a game where Fred Warner and Dre Greenlaw make their presence felt. More importantly, the secondary must get off blocks and make open-field tackles. The linebackers rarely disappoint.

Unless Andy Reid goes against his better judgment, there isn’t a decisive speed advantage like the Detroit Lions’ in the Championship round. Jameson Williams and Jahmyr Gibbs are lightning-fast. Rice has a good burst, but you wouldn’t confuse him with a burner like Williams or Gibbs.

The easiest way to combat an offense that leans on a heavy screen game is by playing man-to-man coverage. You take away the easy throw and force them to get open. During the year, the Chiefs lost more battles than they won when they were 1-on-1. They were 19th in success rate against man coverage.

That’s not something the 49ers do often, as Wilks ran a combination of zone coverage when rushing four at the fourth-highest rate in the league.

Do you remember the Houston Texans Wild Card game against the Baltimore Ravens? DeMeco Ryans had a reputation for blitzing at the league’s lowest rates. Then, he comes out and sends an extra rusher at Lamar Jackson on a whopping 70 percent of plays in the first half. It completely threw the Ravens off their game plan, as the Texans stole half of the football against the No. 1 seed in the AFC.

Historically, you don’t blitz Mahomes. Reid always seems to have a screen up his sleeve to beat the blitz. But this year is different. Kelce isn’t separating like he once was, and Rice, for as well as he’s played, is still a rookie.

Wilks has to get out of his comfort zone to make Mahomes uncomfortable. The loss of left guard Joe Thuney only makes coming after Mahomes more enticing. For a few reasons, Brock Purdy is so successful against the blitz. One is knowing where to go with the football and acknowledging where you have the matchup advantage.

Suppose a team can take away the 49ers’ first or second option; the third one wins. That’s not the case with the Chiefs. When teams rushed five against the Chiefs, they were 26th in EPA per play.

Now, you better get there because Mahomes will buy time and make you pay if you don’t get home. Still, you have to think in terms of how you’re going to win, and mixing in more man coverage and not giving a lackluster Chiefs receiving core soft zones to sit in makes too much sense not to do.

Look no further than the second half in the AFC and NFC Championship games. All of the players said Wilks made the adjustment to run more man coverage, and the Niners kept the Lions out of the end zone until the final drive when it was a two-possession game.

Then Ravens defensive coordinator Mike MacDonald upped the aggression in the second half, and the Chiefs punted on five of their final six drives, with half of those being three-and-outs.

If Mahomes puts together 10-play drives where he methodically marches down the field, then so be it. But the path to a victory doesn’t involve playing passive defense, and Wilks, like the defensive coordinator he replaced, has the perfect opportunity to throw his opponent a curveball. And with the 49ers offense, stealing a couple of possessions in this game could be the difference in winning a Super Bowl.