Exactly who was to blame —and who wasn’t — for Miami Dolphins’ awful run defense Sunday

The Miami Dolphins knew they couldn’t return this season with the same quality of run defense that contributed mightily to a 5-11 season.

And they didn’t.

What they presented in Sunday’s opener at New England was actually much worse.

A Dolphins defense that allowed 135 yards rushing per game last season (26th in the league) was mauled for 217 yards rushing. A defense that permitted 4.5 yards per carry last season (tied for 22nd) relinquished a disheartening 5.2 per attempt.

And this problem better get fixed quickly because after being flummoxed by New England’s Cam Newton, another mobile, scrambling quarterback awaits when Buffalo visits Hard Rock Stadium on Sunday.

Not only did Bills quarterback Josh Allen throw five touchdowns and no interceptions and produce a 115 passer rating in two wins against Miami last season, but he ran for 88 yards on 11 carries — a clip of eight yards per rush.

That’s even better, from a per-carry average, than what Newton did to Miami in steamrolling for 75 yards on 15 carries on Sunday (5.0 per run).

“Josh Allen is big, strong, fast,” Dolphins coach Brian Flores said Monday. “He had [57 yards rushing on 14 carries on Sunday against the Jets]. Some similarities to what we saw yesterday. We’re trying to get a lot of that fixed now, from an edge setting standpoint, from a tackling standpoint, schematically. Hopefully we will work on that over the course of the week from technique, fundamentals and practice standpoint. Hopefully it helps us this week.”

So who’s specifically to blame for Sunday’s run-defense debacle?

Analytics site Pro Football Focus named names on Monday:

▪ Defensive tackle Raekwon Davis.

The Dolphins’ second of two second-round picks in April got the surprising start on Sunday (ahead of Christian Wilkins) and it did not go well.

PFF gave him a dismal grade of 37.6 against the run — worst of any of the 18 players who played on defense for Miami in the opener.

He was on the field for 27 snaps and defended the run on 23 of them and, as PFF, said was “manhandled at times by the New England offensive line.”

The issue with Davis at Alabama in his final two seasons was production not matching talent. In his defense, he was competing against a formidable Patriots interior line anchored by guards Shaq Mason and Joe Thuney and center David Andrews.

▪ The new linebackers, particularly Elandon Roberts, and one returning one.

The Dolphins gambled by choosing Roberts over Raekwon McMillan, who was their top run-stopping linebacker last season. On Sunday, that decision appeared regrettable.

Roberts graded out worse against the run than any player on Miami’s defense except Davis. He played 40 snaps, including 29 against the run.

Miami’s other new linebacker, Kamu Grugier-Hill, was Miami’s third-worst run defender, per PFF, but that doesn’t mean a lot because the Patriots ran on only 9 of his 18 defensive snaps.

As for McMillan, he played only six defensive snaps in his Oakland debut against Carolina. But his run-stopping grades in Miami were infinitely better than what Roberts provided on Sunday.

Meanwhile, Jerome Baker made an impact with 16 tackles, a sack and a forced fumble near the goal-line, but his run-defense grades were eighth-worst on Miami’s defense.

▪ The new established starting edge players.

Perhaps most disappointing on Sunday was the lack of impact from Shaq Lawson and Emmanuel Ogbah. Lawson played 60 of Miami’s 64 defensive snaps and Ogbah 55 of the 64 snaps.

But PFF rated Ogbah and Lawson, respectively, as Miami’s fourth-worst and fifth-worst players against the run, ahead of only Davis, Roberts and Grugier-Hill.

That was both disappointing and surprising, because both Lawson and Oghab ranked very high among edge defenders in PFF’s telling “run stop metric,” which credits a player for a stop if the offense fails to produce a successful play.

On Sunday, Ogbah had one tackle and Lawson three.

▪ Some of Miami’s defensive backs.

Rookie Noah Igbinoghene — who was needed for 37 snaps because Xavien Howard (27 snaps) was on a so-called pitch count — was competent in coverage but struggled in the running game. He was Miami’s sixth-worst run defender.

The two veteran safeties, Eric Rowe and Bobby McCain, finished 9th and 10th respectively, in run defense.

▪ Davon Godchaux.

He graded out seventh-worst against the run on a three-tackle day. The good news is that two of his tackles were stops, which are tackles that constitute a loss for the offense based on that aforementioned PFF stat. Last season, Godchaux led all NFL interior linemen with 32 stops.

Overall against the run, Flores said: “There were obviously a lot of issues. So setting the edge, those quarterback read plays, who’s got the quarterback. There was some miscommunication on that. We tried to get it fixed on the sideline. Got it fixed. One guy’s got it; somebody else doesn’t have it. There were a plethora of things we’ve got to get fixed. That falls on me. We’ll get that corrected.”

So who graded out well against the run? Chistian Wilkins, who not only was Miami’s best run-stopper Sunday, but filled the box score with six tackles, a sack, two tackles for loss and two passes defended.

Miami’s second- and third-best run defenders were nickel cornerback Jamal Perry and safety Brandon Jones.