NFL

5 X-Factors for Super Bowl LIV

We're just a couple of days away from the final NFL game in seven months. Let that sink in.

The good news is, this matchup *should* be a doozy. The contest features two teams that were inside the top-five in points per game in 2019 -- teams that also happen to be averaging 37.5 points in their four combined postseason games. And, unless you're a boomer, a lot of points usually equals a lot of fun.

With that in mind, it's time to look at what will be the biggest individual matchups and factors in the biggest game of the year. Here are five major keys to the game:

1. San Francisco's Rushing Attack

Logically, the best way to beat Patrick Mahomes and the Kansas City Chiefs is to dominate on the ground. If you do it well, #EstablishingTheRun can accomplish two things: 1) It allows you to win the time-of-possession battle, which in turn allows you to, 2) Keep the ball out of the 2018 MVP's hands.

Kansas City has lost eight games with Mahomes behind center. On average, they were out-gained 168.9 to 79.1 on the ground in those contests. That's essentially a 90-yard difference. As is to be expected, they lost the time-of-possession battle by an average of 8 minutes and 54 seconds in those defeats.

This season, the Chiefs ranked fifth in Adjusted Defensive Passing Net Expect Points (NEP) per play. Comparatively, they were fifth-worst in Adjusted Defensive Rushing NEP per play. The conclusion here is as simple as 1 + 1 = 2.

If the San Francisco 49ers have proven anything over the second of the season, it's that they can ram the ball down the opposition's throats. Over their last eight games (including the playoffs), the Niners are averaging 160.8 rushing yards, 5.4 yards per carry, and 2 rushing scores per contest. That kind of rushing success will play well with their ultra-efficient, fifth-ranked passing offense (in terms of Adjusted Passing NEP per play).

2. Travis Kelce

Like Rob Gronkowski was before him, Travis Kelce is an absolute nightmare matchup for most defensive coordinators. He's too big and strong for most corners and safeties, and he's too fast for most linebackers.

With that in mind, it should come as no surprise that, for the most part, when Kelce has success, so do the Chiefs. With Mahomes as signal-caller, Kelce has had more than 75 yards in 18 of their 25 victories. However, in their 8 losses, he topped that number just once.

In 2019, no team allowed fewer yards to the tight end position than the Niners. But there's more -- 42 percent (231) of the 552 yards and half of the touchdowns that San Francisco surrendered to the position came in the four games that strong safety Jaquiski Tartt was not on the field.

San Francisco also has the added benefit of having three 'backers -- Kwon Alexander, Dre Greenlaw, and Fred Warner -- that excel in coverage. According to Pro Football Focus, 69 (nice) linebackers had at least 200 snaps in coverage, and each of those aforementioned three found themselves inside the top-15.

More so than perhaps any other team in the league, the 49ers are equipped to, at the very least, slow down Kelce -- which could result in a Niners victory.

3. Slot Defense

According to Pro Football Focus, the 49ers and Chiefs were the league's two best teams when targeting slot receivers and inline tight ends. Which means this game could come down to who does a better job of covering the middle of the field.

At linebacker, San Francisco has the clear advantage. As mentioned before, Niners have three 'backers inside the-15 in coverage grades. That allowed defensive coordinator Robert Saleh to go with his base or nickel packages for 98.7 percent of their regular-season defensive snaps. Meanwhile, the Chiefs don't have a single linebacker inside the top-25 as far as coverage is concerned. The result? Kansas City played dime nearly 50 percent of the time -- more than any other team in the league.

What the Chiefs do have is Tyrann Mathieu. Since he entered the league, Mathieu has been and continues to be, one of the league's premier slot defenders. According to Pro Football Focus, 42 corners saw 25-plus targets in the slot -- only two allowed a lower passer rating on those targets than the Honey Badger (70.0).

Unfortunately for the Chiefs, one of those two who allowed a lower passer rating than Mathieu happens to play for the team they're facing. San Francisco slot corner K'Waun Williams finished the season second in passer rating allowed (69.3) and sixth with a slot coverage grade of 76.5. Speaking of Williams, he'll get to see a lot of the next x-factor on this list, which is...

4. Tyreek Hill and Mecole Hardman

4.28 and 4.33. Those are the unofficial and official timed speeds of Tyreek Hill and Mecole Hardman.

Mano-a-mano, the 49ers can't beat that. Richard Sherman ran a 4.56 when he came out -- he's probably slowed a bit since. Their other outside corner, Emmanuel Moseley, ran a 4.42. The aforementioned K'Waun Williams ran a 4.53. Free safety Jimmie Ward ran a 4.47. Finally, strong safety Jaquiski Tartt ran a 4.53.

Working in San Francisco's favor is the fact that they only play strict man coverage 26 percent of the time. However, nearly half -- if not more -- of their coverages have some man-to-man concepts. Consequently, the stark difference in speed should factor in on Sunday.

San Francisco will likely have a plan for Hill -- though many teams have had plans for him only to get punched in the mouth.

The real wild card is Hardman. As Jim Sannes observed in his Situations to Monitor piece, Hardman ran 22 routes in the Conference Championship game against Tennessee -- his most in any game with Hill healthy. The rookie is quite capable of making the big play. As noted by Brandon Gdula, of the 108 players to garner at least 10 downfield targets, Hardman ranked third in Reception NEP per target, at 1.94.

The speed of these two could swing the outcome of the game on Sunday, quickly.

5. 49ers Defensive Line vs. Chiefs Offensive Line

San Francisco doesn't blitz often. In fact, they ranked 29th in the league with a blitz rate of 20.9 percent.

Of course, when you have a defensive line that includes Nick Bosa, DeForest Buckner, Dee Ford, and Arik Armstead, you really don't need to send extra rushers.

According to Pro Football Focus, of the 60 edge defenders with at least 560 snaps, Bosa (7th) and Armstead (21st) both ranked inside the top-25 in pass rush. That doesn't include Ford, who would've ranked 23rd had he played enough snaps. Buckner ranked 11th in pass rush among the 47 interior defenders who qualified under that same criteria. In summary, this group can get to the quarterback without needing to blitz.

This is key because, according to NFL.com's Next Gen Stats, Mahomes has a career 116.5 passer rating when the opposing team sends five or more rushers. You just can't beat him with the blitz.

Mahomes' rating against four rushers or less is still stellar, though it is 7.5 points lower, and he hasn't faced many teams that are this effective rushing four.

During the regular season, Kansas City's offensive line was about average in ESPN's pass block win rate (14th). They also ranked fifth-worst in Football Outsiders' adjusted line yards. Right tackle Mitchell Schwartz is the star of this group, with PFF pass and run block grades above 83. Left tackle Eric Fisher allowed just one sack in 2019, though he appeared in just eight games -- he had surrendered an average of 6.7 sacks per season prior to this one. Left guard Steven Wisniewski graded out as the team's best pass blocker, though he only started four games for the team. Center Austin Reiter and right guard Laurent Duvernay-Tardif graded average-to-below-average, according to PFF.

This unit will need to bring their A-game against a 49ers line with the second-best adjusted sack rate in the league.