When the San Francisco 49ers and Kansas City Chiefs square off Sunday in Miami Gardens, each team’s head coach will be vying for a shot at redemption.
In his seventh season with Kansas City, Andy Reid has led the Chiefs to a 12-4 regular-season record and their first Super Bowl appearance since the 1969 season. Though he’s guided two franchises to seven conference championship games, Reid has only coached in one other Super Bowl – when his Philadelphia Eagles lost to the New England Patriots at the end of the 2004 season.
On the opposite sideline, Kyle Shanahan, who led San Francisco to a 13-3 record in his third season as head coach, will coach in the Super Bowl for the first time since serving as the Atlanta Falcons’ offensive coordinator during the 2016 season. In Super Bowl LI, Shanahan’s offense held a 25-point lead over the Patriots with under three minutes remaining in the third quarter but failed to score another point as the Patriots stormed back and won 34-28 in overtime. For both Reid and Shanahan, a Super Bowl win would be instrumental in rewriting their playoff legacies.
There’s little doubt that San Francisco’s ability to slow Patrick Mahomes, the 2018 NFL MVP, will play a key role in determining whether Shanahan comes out on top. Among quarterbacks who have attempted at least 350 passes this season, the 24-year-old Mahomes has a Well-Thrown% of 81 on his 531 pass attempts – which trails only Drew Brees (85.3%) and Derek Carr (85%). Well-Thrown% measures how often a quarterback throws the ball accurately (for example, he leads the receiver when he’s supposed to or hits the back shoulder when needed). In four career playoff games, Mahomes has a 115.0 passer rating and 11 passing touchdowns – the most in NFL history by a quarterback with no interceptions.
The 49ers, however, feature a formidable pass rush, led by edge rushers Nick Bosa, Dee Ford and Arik Armstead, and defensive tackle DeForest Buckner. Excluding free pressures where he went unblocked, Bosa has compiled 63 pressures in his rookie season on 237 pass rush opportunities—pressuring the quarterback 13.5% more often than the average rate at his position. Ford, who was traded to San Francisco in the offseason after five seasons with Kansas City, will also try to make his former teammate uncomfortable in the pocket. Ford’s 23 pressures in 88 pass rush opportunities (also excluding free pressures) is a rate 13.7% better than average at his position. Armstead led the 49ers with 10 sacks and 11 tackles for losses, and Buckner’s 49 pressures in 248 pass rush opportunities, excluding free pressures, is 9% better than expected for a defensive tackle.
As a result, opposing offensive lines have just a 26.2 Protection Index against the 49ers – 20 points below the NFL average and almost 10 points lower than the Miami Dolphins’ offensive line, which allowed an AFC-high 58 sacks. The Protection Index is a proprietary formula created by Stats Perform that measures pass protection by using metrics such as length of passes, sacks allowed, quarterback hurries and knockdowns, and penalties by offensive linemen.
Unfortunately for the 49ers, Mahomes and the Chiefs might be better prepared to face their fierce pass rush than anyone in the league. Mahomes has the fourth-highest QB rating in the NFL when facing a blitz at 127.4 with seven touchdowns and no interceptions. Up front, the Chiefs have allowed just three sacks in blitz passing situations all season – the fewest in the NFL – and have the second-highest Protection Index after the Dallas Cowboys. Kansas City’s line rates above average at every position except left tackle, where Eric Fisher has allowed 6.3% more quarterback pressures than the average player at his position.
Should the Chiefs fend off the 49ers’ league-best pass rush, Mahomes will then have to deal with a San Francisco secondary that has limited opponents to a league-low 169.2 pass yards per game. As one way to measure a secondary’s effectiveness, Stats Perform has developed a metric called Burn Rating, which takes into account factors such as passing yards allowed and big passing plays allowed and is comparable to a quarterback rating for pass coverage. The 49ers have an above-average Burn Rating against every type of receiver, including a league-leading -12.4 rating against tight ends (meaning they are over 12 index points better than the league average). Mahomes, therefore, may have limited opportunities to connect with Travis Kelce, who led all tight ends with 1,229 receiving yards during the regular season.
Kansas City wideout Tyreek Hill will present an entirely different challenge for the 49ers’ secondary. Hill, nicknamed “Cheetah” for his blazing speed, has gotten open on an astonishing 53.8% of his one-on-one matchups, far higher than the average NFL receiver (32.8%). Even when he is not the primary target, Hill draws extra attention that could create other opportunities. Hill faced 22 true double teams this year, more than twice as many as Kelce.
San Francisco is equipped with the defensive talent to blanket Kansas City’s receivers. Richard Sherman, who was selected to his fifth Pro Bowl, has only been beaten 21 times in 95 one-on-one matchups – a rate over 8% better than the average for cornerbacks. In the limited opportunities that 49ers’ linebackers have played one-on-one coverage as a result of their zone-heavy approach, the trio of Fred Warner, Kwon Alexander and Dre Greenlaw has only been beaten 10 times in 47 opportunities for a percentage over 9% better than the average for linebackers in single coverage. Emmanuel Moseley, who has replaced struggling cornerback Ahkello Witherspoon in the starting lineup, has been below average in pass coverage as well, getting beat 38.5% of the time in one-on-one matchups. Expect Mahomes to thoroughly test Moseley through the air.
On the other side of the ball, Kansas City faces the challenge of trying to slow San Francisco’s vaunted running game. The 49ers are averaging 235.5 rushing yards in the playoffs, the most in a span of two or more games of a playoff run since the Chicago Bears averaged 242 in 1941. Tevin Coleman’s availability remains a question mark, though, due to a dislocated shoulder he suffered in the division round against the Minnesota Vikings. The injury gave Raheem Mostert an opportunity to carry the load in the NFC title game, and he rushed for 220 yards and four touchdowns as the 49ers defeated Green Bay 37-20. Regardless of Coleman’s status, Mostert figures to be the focal point of San Francisco’s running game. He’s been difficult to bring down, forcing 45 missed tackles on 194 touches this year – the most of any player in the Super Bowl.
Kansas City has struggled to defend the run, giving up 128.2 rushing yards per game – 26th in the NFL. However, defensive tackles Chris Jones and Mike Pennel (who was signed in October after he was cut by the Patriots) and defensive end Frank Clark have been effective against the run, combining for 98 Run Disruptions in 460 run snaps. That’s collectively 26.5% higher than the expected rate at those positions. Stats Perform’s Run Disruption is considered any action that causes a run play to be stopped or re-directed. If Jones and Clark can anchor Kansas City’s run defense, San Francisco’s ground game could face its toughest challenge of the playoffs.
Because of their heavy reliance on running the ball, the 49ers haven’t asked for much from quarterback Jimmy Garoppolo in the playoffs. Garoppolo’s eight pass attempts in the NFC Championship against Green Bay were the fewest by a team in a playoff game since Bob Griese of the Miami Dolphins attempted just seven in a Super Bowl VIII victory on Jan. 13, 1974. The 49ers’ limited usage of Garoppolo has spurred debate about whether he’ll be able to take the offense into his own hands if necessary. But San Francisco was 7-0 this season when Garoppolo threw for over 250 yards, his 115.7 passer rating when his team was losing was the second-highest in the league and the 49ers were third in the NFL with 39 completions of 25 or more yards.
Deebo Samuel and Emmanuel Sanders have faced single coverage more often than all other 49ers skill position players combined and have both been slightly below average in terms of getting open in one-on-one matchups. In fact, the only wide receiver on the 49ers who gets open in one-on-one coverage at an above-average rate is Kendrick Bourne, who wins 40% of those matchups. He’s most often targeted in the red zone, evidenced by his six touchdowns on only 34 overall receptions in both the regular season and playoffs. Despite his mediocrity at getting open against one-on-one matchups, Samuel has forced a missed or broken tackle on 40.5% of his 79 offensive touches—over 25% better the NFL average for wideouts (14.9). As a result, he averaged 8.4 yards after catch (YAC), second to only Titans’ rookie A.J. Brown (8.9) among all receivers.
Like the Chiefs, the 49ers’ most reliable target is their tight end. George Kittle has beaten his man and gotten open 23 times in 64 one-on-one matchups this season, a percentage over 7% higher than the average NFL tight end, and tied for first place (along with Kelce) among tight ends with 6.1 receptions per game. Kittle faced nine double teams this season – no other 49er faced more than one.
However, the Chiefs have been solid at covering tight ends with a Burn Rating that’s over 8 index points better than league average. Overall, Kansas City has allowed an 80.8 passer rating to opposing quarterbacks – the fifth-lowest mark in the league. The Chiefs have an above-average Burn Rating against every type of receiver except running backs, for which they have been over 5 index points worse at covering than average. For that reason, Shanahan might look to get Mostert or Coleman open in the flat to gain significant chunks of yardage.
At this point, those who have been following the playoffs know the strengths, weaknesses and strategies of Reid’s Chiefs and Shanahan’s 49ers. The Chiefs will likely try to get Mahomes going through the air and take advantage of the 49ers’ tendency to rush the quarterback by finding gaps in coverage that open up as a result. Shanahan and the 49ers will likely look to continue moving the ball on the ground with a combination of Mostert and Coleman (assuming he plays) since the Chiefs have not been particularly successful against the run. However, if the Chiefs can take the running game away from San Francisco, their fate will depend on Garoppolo’s arm. While he’s shown flashes of greatness early in his career, Garoppolo can place himself among the leagues’ top-tier quarterback with a memorable performance on the biggest stage.
Advanced analytics and data analysis provided by Stats Perform’s Kyle Cunningham-Rhoads