If every Super Bowl offers insights about the NFL’s past, present and future, the New England Patriots’ sixth title typified the lesson that has become as dull and resounding as their 13-3 triumph Sunday over the Los Angeles Rams.

The Patriots still have Bill Belichick and Tom Brady, and no one else does, and that’s usually enough.

A year after losing a shootout to the Philadelphia Eagles, New England won Super Bowl LIII with defense, a game that was half-slugfest, half-punting battle. Two years after running off a 25-point comeback against the Atlanta Falcons, the Patriots all but sat on the Rams and waited for the game to end and the confetti to fall.

On a macro level, New England’s infrastructural advantages — a quarterback and a coach with claims to being the sport’s greatest ever — are unmatched. But as the Ravens approach free agency and the draft, there are lines in the champions’ blueprint worthy of closer examination.

If the Ravens want to build on last season’s playoff run, want to build a Super Bowl contender, they can look to how the Rams got to the precipice — and how the Patriots have kept their dynasty alive.

1. Every good offense should have a good slot receiver.

Super Bowl Most Valuable Player Julian Edelman had a performance so awesome (10 catches for 141 yards), it thrust his 10-season, no-Pro Bowl career into Hall of Fame consideration. He was a safety blanket for Brady all year, with 48 receptions in the slot during the regular season, 11th most among wide receivers, according to Pro Football Focus.

It was no coincidence that one of the NFL’s best offenses succeeded only when its slot receiver did. The Rams offense was not the same after Cooper Kupp tore his ACL in November. From the 10 regular-season games with their star slot receiver to the six without, quarterback Jared Goff’s average yards per pass dropped nearly 3 yards, his accuracy fell over 8 percent, and his passer rating went from Patrick Mahomes-esque (113.0) to Joe Flacco-esque (83.9).

A quality slot receiver unlocks a passing offense’s potential. According to Football Outsiders, some of the NFL’s most efficient routes are those typically run by slot receivers: digs, slants and seams. Fades and out routes, usually the province of receivers split wide, are among the least efficient. Throws to inside receivers are generally safer, requiring less arm strength and timing, than those aimed near the sideline.

For as often as the Ravens struggled through the air, Willie Snead IV was nothing if not a reliable target for Flacco and, later, Lamar Jackson. The first-year Ravens receiver finished with over 500 receiving yards from the slot, according to ESPN, an impressive total made even more so by the offense’s midseason switch to a run-first offense. Snead is only 26, and an offseason with Jackson should only improve their chemistry.

He might not even be the Ravens’ best slot receiver by year’s end. The position is open to tight ends, too, and perhaps especially so in coordinator Greg Roman’s schemes. The Kansas City Chiefs’ Travis Kelce was one of the NFL’s most dangerous slot receivers for much of last season, too big for safeties and too fast for linebackers to cover. If Mark Andrews and Hayden Hurst continue their rookie-year development, they’ll make life much easier for Jackson.

2. There’s no better front-office help than a quarterback on a bargain deal.

The four starting quarterbacks in the AFC and NFC championship games all finished among the NFL’s top 12 overall in passer rating. None are among the league’s six highest paid at the position.

The New Orleans Saints’ Drew Brees, with an average annual salary of $25 million, is the foursome’s top earner, at No. 7 overall. The rest — Brady ($20.5 million), Goff ($7 million) and the Kansas City Chiefs’ Mahomes ($4.1 million) — all make less than Flacco.

All four deals are bargains, none more so than the two rookie contracts. Consider that the the Chiefs are now paying the NFL’s reigning Most Valuable Player $24 million less per year than the Vikings are Kirk Cousins. Those savings add up.

In New England, the Patriots have allowed Belichick to re-sign the team’s best players, a strategy of retention that Ravens general manager Eric DeCosta prioritized at his introductory news conference. Over the past seven years, they’ve signed tight end Rob Gronkowski, Edelman, cornerback Devin McCourty, kicker Stephen Gostkowski, right tackle Marcus Cannon and linebacker Dont’a Hightower to multiyear extensions.

The Rams, unencumbered by a big-money quarterback contract, spent lavishly last offseason, signing free-agent defensive tackle Ndamukong Suh to a one-year, $14 million contract, absorbing cornerback Aqib Talib’s $11 million salary in a trade and (briefly) making homegrown defensive tackle Aaron Donald the highest-paid defensive player in NFL history.

In parting ways with Flacco, either in a trade or by cutting him, the Ravens will have to take on significant dead money: either $8 million in 2019 and 2020 or $16 million in 2019. But there will be relief after that. Jackson’s cap hit won’t exceed roughly $3 million over the next three seasons — Flacco’s won’t be less than $24.3 million over the same span — and the Ravens can exercise Jackson’s fifth-year team option in 2022.

The front office cannot predict Jackson’s development as a quarterback. But it should have the salary cap space to build out the team around him.

3. Control the line of scrimmage, and good things will follow.

There’s no one way to build an elite offensive line. The Patriots’ front five was largely homegrown, with no one drafted higher than the third round. The Rams’ had some imports, and three second-round picks overall. But both excelled.

The New England and Rams units finished as the NFL’s fourth and sixth best in the regular season, respectively, according to Pro Football Focus. They combined to allow one sack in their respective divisional-round and conference championship games. It was no wonder their teams found themselves in the Super Bowl.

Over the past four seasons, just one team that made the Super Bowl did not have an offensive line not rated among the NFL’s 10 best by PFF. The Denver Broncos finished tied for 20th in their 2015 championship season, a year marred by the loss of left tackle Ryan Clady and replacement Ty Sambrailo to season-ending injuries. (They compensated with a defensive front that deep-fried offensive lines themselves.)

The Ravens are not in a bad place up front; they earned PFF’s No. 9 overall ranking. Left tackle Ronnie Stanley was named a Pro Bowl alternate, rookie Orlando Brown Jr. was a revelation at right tackle, and guard Marshal Yanda outperformed both.

But with Yanda’s career likely nearing an end and improvements needed at left guard and center, be it via internal upgrades or external acquisitions, the Ravens’ front office cannot afford to neglect the team’s line. It is not only Roman’s running game that depends on it but also the health and safety of Jackson. And it’s hard to win a Super Bowl with no quarterback.

jshaffer@baltsun.com

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