Now let’s be clear: The Dolphins’ offense shoulders much of the blame for the team’s collapse from 8-3 to 8-8.

During this ongoing five-game losing streak, Miami has averaged 20.8 points, a figure that would rank 21st in the league during the entire season and is significantly below the 24.1 points that the Dolphins have averaged overall this season (10th best in football).

But this much also has been established: This defense cannot be trusted in moments of truth. During this five-game skid, Miami’s defense has allowed long, clock-chewing, point-producing fourth quarter drives in all of them. Consider:

▪ Against the 49ers, after the Dolphins failed to convert a fourth down when trailing 23-17 and 6:03 left, the Dolphins defense allowed a 10-play, 34-yard drive (taking up 3:57), highlighted by a Christian McCaffrey 30-yard run, setting up a Robbie Gould field goal that pushed the 49ers’ lead to 26-17 with 2:03 left and essentially settled matters.

▪ Against the Chargers, the Dolphins punted when trailing 20-14 with 11:09 left. The Chargers then drove 79 yards on 17 plays, chewing up 8:39 on the clock, with Justin Herbert completing 5 of 6 passes during that stretch (to go along with a 10-yard run) and Austin Ekeler scampering for 10- and 12-yard runs.

Along the way, Los Angeles converted a third-and-5, third-and-3 and third-and-8. That drive ended with a 28-yard Cameron Dicker field goal that made it 23-14 with 2:40 left, essentially sealing the game.

▪ Against the Bills, after punting from the Bills 43 in a tie game with 6:04 left, Miami watched Buffalo go 86 yards on 15 plays in 6:04 to set up Tyler Bass’ 25-yard game-winning field goal as time expired.

On that drive, Devin Singletary ran six times for 34 yards and Josh Allen was four for five for 40 yards, and picked up a key 21-yard pass interference penalty on Kader Kohou.

▪ In the Green Bay game, after a Tua Tagovailoa interception at the Green Bay 30 with 6:07 left (and the Dolphins down 23-20), the Packers drove 56 yards on nine plays, taking up 4:00, to set up Mason Crosby’s 26-yard field goal that made it 26-20 with 2:02 left.

Aaron Rodgers completed two passes for 35 yards and Aaron Jones burst out on an 18-yard run on that drive.

▪ Against a subpar New England offense, the Dolphins again capitulated on Sunday. Down 16-14 with 9:43 left, Miami allowed New England to march 89 yards on 11 plays, using up 5:00, for a game-sealing TD. Mac Jones completed five of seven passes for 51 yards and a TD, and drew a Keion Crossen 22-yard pass interference penalty on that drive.

In the Dolphins’ defense, they played all five of these losses without Byron Jones, Nik Needham, Emmanuel Ogbah and Brandon Jones, and on Sunday were also without Xavien Howard and Bradley Chubb.

Nevertheless, the lesson to emerge is self-evident: The Dolphins defense cannot be trusted with the game on the line. Overall, the defense is allowed 24.6 points per game, 27th in the league.

“In general, we’re not playing as well as we should be with the talent that we have, with the coaching staff that we have, with the bond that we have,” Jaelan Phillips said last Monday.

THIS AND THAT

The Jets-at-Dolphins game will be played at 1 p.m. Sunday on Fox, at the same time the Patriots are playing Buffalo on CBS. Miami needs a win and Patriots loss at Buffalo to make the playoffs.

▪ Notable snap counts on offense Sunday: Tight end Durham Smythe plays more snaps than Mike Gesicki for the fifth game in a row (42 to 30), but Gesicki’s 30 were his most during this five-game losing streak…Running back Jeff Wilson Jr. played significantly more than Raheem Mostert (46 snap to 30), which was unusual since Wilson’s acquisition from the 49ers….

Fullback Alec Ingold, playing with a cast over his injured thumb, was limited to 11 snaps… Quarterback Skylar Thompson played 27 snaps in relief of Teddy Bridgewater, who played 44… Receiver Trent Sherfield, the intended receiver on Bridgewater’s pick-six to Kyle Dugger, played 42 snaps, compared to 11 for Cedrick Wilson Jr… Left tackle Greg Little played 39 snaps in relief of Kendall Lamm, who played 32 before leaving with an ankle injury.

▪ Notable snap counts on defense: With Chubb sidelined by ankle and hand injuries, Andrew Van Ginkel played 38 snaps and Melvin Ingram 28… With Howard sidelined by a knee injury, Keion Crossen and Kader Kohou played 59 of Miami’s 60 defensive snaps, Noah Igbinoghene played 30 and Elijah Campbell 7… Linebacker Duke Riley, who allowed Jakobi Meyer’s 1-yard game-sealing TD catch, again played limited defensive snaps (five)...

Defensive tackle Josiah Bronson played five snaps in his Dolphins debut, but Brennan Scarlett (who, like Bronson, was also elevated from the practice squad) did not play any defensive snaps… Justin Bethel, Sam Eguavoen and Channing Tindall were used only on special teams - not on defense.

▪ Dolphins kicker Jason Sanders, who began his career making 12 of 15 field goals of 50 yards or more, is just 3 for 11 on those types of kicks this season, including 1 for 5 this season. Wind was a factor on his missed 51-yarder in the second quarter against the Patriots.