In some ways, it’s not surprising to see the Kansas City Chiefs and Philadelphia Eagles facing off in Super Bowl LVII. These two teams are pretty familiar with the championship limelight, as both have been to (and won) the big game recently — the Eagles after the 2017 season and the Chiefs after the 2019 season. This season, both teams were 14-3 and earned their conference’s top seed, setting up just the eighth battle of No. 1s in the Super Bowl since the NFL playoffs expanded beyond a 10-team field in 1990.

What is unusual, however, is the stark contrast in how the Eagles and Chiefs got back to the championship. In the former, we have a team making Super Bowls five years apart with two different quarterbacks and two different coaches; in the latter, a team that’s in its third Super Bowl in four seasons with only marginal changes to its overall scheme and personnel. So in that sense, it’s worth looking at all the things that have — and haven’t — changed for both teams relative to their Super Bowl-winning predecessors, to get a sense for whether chaos or continuity will win the day. 

Let’s start with the Eagles, who are more removed from their latest Super Bowl appearance.  Again, the calendar says it has been five years — but in terms of the franchise’s evolution, it feels like a lot longer. When Philadelphia took the field against the New England Patriots in Super Bowl LII, the quarterback was Nick Foles (standing in for injured starter Carson Wentz) and the coach was Doug Pederson; now those roles are being filled by Jalen Hurts and Nick Sirianni, respectively. Among teams who made Super Bowls within five years of each other, the Eagles are only the fourth in history to have both a different QB and a different coach in their return trip.

Despite the changes on the sideline and under center, the 2022 and 2017 Eagles have similar overall resumes of success. Both versions went 16-3 (including playoffs), while scoring and allowing nearly identical points per game.¹⁶ But there are major stylistic differences in how each team handled its business along the road to the Super Bowl, some of which speak to the philosophical differences between Sirianni and Pederson (despite Sirianni coming from the coaching tree of Frank Reich, who was Pederson’s offensive coordinator with the Eagles in 2017).

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According to schedule-adjusted expected points added (EPA) per game, the 2017 Eagles had the league’s second-best passing attack (+7.0 EPA/game relative to league average) with Wentz directing the offense for 13 starts before Foles took over in relief. Philly’s ground game, however, was mediocre, ranking 20th (-0.3 EPA/game) with an ensemble of ball carriers running behind a line that finished 24th in ESPN’s run block win rate statistic.

By contrast, the 2022 Eagles have achieved much greater balance between passing and rushing productivity. They rank 11th in passing EPA/game (+1.7), driven by the efficiency of Hurts at QB and the star tandem of A.J. Brown and DeVonta Smith at receiver, and they also lead the league by a mile in rushing EPA/game (+3.7). Hurts’s dual-threat abilities combined with the running of Miles Sanders and the league’s second-best run-blocking line by win rate to create an offensive machine that can beat opponents in more ways than the 2017 squad could. (Which is scary, considering that team produced the eighth-biggest offensive explosion in Super Bowl history — 41 points — against the Patriots.)

Where the two teams are far more similar is on defense, which saw the 2017 Eagles rank fifth overall (No. 5 against the pass and No. 16 against the run) in 2017 and fourth overall (No. 1 against the pass and No. 23 against the run) in 2022. The current Eagles are well known for their dominant pass rush, which produced a whopping 70 sacks during the regular season — and knocked not one, but two San Francisco quarterbacks out of the NFC title game — and they led the league in pass rush win rate (52.7 percent). But it must be noted that the 2017 Eagles also led the league in pass rush win rate, with an even greater success percentage against opposing blockers (59.2 percent). That was the highest rate by any team in a season since 2017, the earliest season for which ESPN has data, and it serves as a reminder of just how long Philly has been striking fear into the hearts of opposing QBs.

While the Eagles have experienced a series of peaks and valleys since their last Super Bowl run, the Chiefs have consistently been excellent. (You don’t host five straight AFC championship games without being pretty good year in and year out.)

It’s particularly noticeable on the offensive side. Since Patrick Mahomes took over as the starter in 2018, the Chiefs have ranked either first or second in EPA per game. This is largely due to the magic Mahomes works behind center: Other than a slightly “off year” in 2020, when it finished the season ranked third behind the Buffalo Bills and Green Bay Packers, the Chiefs’ passing offense has led the league in each of the past five seasons. In fact, the numbers the passing game posted in 2018 (+10.2 EPA/game), 2019 (+9.1) and 2022 (+9.1) are the best three team-season performances in the past five seasons. At the same time, the Chiefs’ ground game has remained in the middle third of the league, clocking anywhere from -0.2 to +0.6 EPA/game relative to league average in the past four seasons.

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While the 2019 and 2022 offenses have some clear similarities — the ubiquity of tight end Travis Kelce, the team’s leading receiver in three of the past four seasons, is the most obvious one — it’s not the exact same team. The team has made small strides in the trenches: After finishing with the 19th-best pass rush win rate in 2019 (40.9 percent), Kansas City was ranked 15th this season (41.4 percent). And the 2019 Chiefs were a more vertical passing offense, with receiver Tyreek Hill streaking down the field on 39 percent of his routes and Mahomes hurling 13.4 percent of his passes at least 20 air yards down the field. Since shipping Hill to Miami, however, only 8.8 percent of Mahomes’s attempts have traveled at least 20 air yards. 

Still, targeting shorter routes hasn’t cost the Chiefs anything in the way of efficiency, as they put up almost 29 points a game this season — basically the same figure as they have since 2019.

The strength of the Kansas City offense has disguised some fluctuations in the defense and special teams. Led by a rangy secondary that featured Tyrann Mathieu and Charvarius Ward, the Super Bowl champion team had the 13th-best defense by adjusted EPA/game. But since that season, when the defense averaged +1.1 EPA/game, the Chiefs defense hasn’t finished with a positive EPA/game relative to league average. That’s largely due to the team’s struggle to stop the run, though there’s been some good news for Kansas City on that front: After ranking 28th and 30th in run defense EPA/game in the 2019 and 2020 seasons, the team has improved to 23rd and 24th the past two seasons.

As the offense has soared to new heights and the defense drifted slightly below average, Kansas City’s special teams have been pretty inconsistent, rising from 14th (2019) to seventh (2021), but then slipping all the way to 30th (2022) in EPA/game. Kicker Harrison Butker made a career-low 75 percent of his field goal attempts this season, after averaging 90.3 percent in the prior three seasons. But again, it’s a testament to Mahomes and the strength of the Chiefs offense that the team has seen no drop-off in overall scoring despite leaving more points on the field. 

All told, neither the Eagles nor the Chiefs are exact replicas of their last Super Bowl-winning editions. And that’s not surprising. It is the nature of the NFL to weaken strong rosters and force successful clubs to adapt; after all, 31 other teams are out to topple the champ from its pedestal each season. Some must change more than others — Philadelphia has undergone an extreme makeover, while K.C. has had just a little bit of work done — but both Super Bowl combatants serve as a testament to the constant process of refinement that builds a championship-caliber team.

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