Allen Park — After a two-week, holiday-related break from the film review, we return just in time to dissect the Detroit Lions' 30-16 loss to the red-hot Los Angeles Rams.

The margin of defeat ended up being right about where most anticipated, but the way the Lions lost the game probably didn't follow the expected script

The Lions managed to keep it close until halfway through the fourth quarter, when quarterback Matthew Stafford fumbled and the Rams converted that turnover into a touchdown a few plays later.

Before that, Detroit's defense managed to limit the high-powered Rams offense to 16 points. We'll explore how the unit was able to accomplish that as part of this week's five observations from the film. 

Buzz coverage, bad Goff

The Lions threw a variety of coverage looks at the Rams offense, with a clear premium placed on stopping the vertical elements of the passing attack. Coming into the game, the Rams were averaging a league-best 9.3 yards per passing attempt, so there was an understandable focus on limiting that. 

Throughout the first half, the Lions leaned heavily on a Cover-3 buzz defensive look, with the two outside corners and the deep safety splitting the field into thirds, with the other safety, the buzz defender, matching up in man with a receiver in the middle of the field, regardless of whether that route stemmed vertically or broke laterally. The coverage look essentially adds a dimension for a quarterback to navigate between the zone layers. 

The best example of that coverage's usage came on Quandre Diggs' interception during the second quarter. 

On the 1st-and-10 snap, the Rams ran play action with wide receivers Brandin Cooks and Robert Woods running vertically at the snap. Woods, from the right slot, broke his route at 12 yards on a post pattern (that developed into an escape route). He was picked up by the buzz safety Glover Quin.

Cooks ran a deeper post, from the left side, stemming at 16 yards and continuing across the field. 

Despite the fact Cooks was bracketed by Diggs and Darius Slay in the Cover 3, Rams quarterback Jared Goff heaved the deep shot to his 5-foot-10 speedster. Slay should have picked it, but misjudged the throw's depth and had it sail over his head. Diggs, meanwhile, tracked the errant throw well from the trailing position to snatch his second interception of the year.

More: After Darnold disaster, Lions get two more shots at elite rookie QBs

Goff, who is in the thick of the MVP race, had a rough day overall. He missed on a number of throws, often wide, occasionally long, routinely costing the Rams. He overthrew tight end Gerald Everett on the opening series after Diggs stumbled in coverage, was long to Woods down the left sideline when the receiver was one-on-one with Nevin Lawson and missed wide on a throw to Josh Reynolds in the end zone, leading to the Rams settling for a field goal.

That was just the first quarter. Goff misfired on four other throws to open receivers, including twice in the red zone. It was a surprisingly bad day for the third-year passer. 

Struggling Slay

A few times each week someone reaches out, whether via social media or email, to ask if Slay is playing hurt. While he hasn't appeared on the injury report the past two weeks, it certainly has been a rough year for the All-Pro. He has missed practice time with a concussion, toe and knee injuries. 

The knee issue cost him a game and lingered for several weeks. And while I wouldn't count on him or coach Matt Patricia commenting on it anytime soon, I wouldn't be surprised to hear it's still bothersome.

Even though Slay hasn't looked himself this season, he's still been solid most weeks. That wasn't the case against the Rams, when he turned in his worst performance since getting worked over by Davante Adams in Week 5. 

Slay is a complete cornerback, but his calling card is his speed, and that's what was missing against the Rams. After drawing a pass interference flag on the opening series, and allowing a 19-yard completion to Woods on a tightly contested deep out, the Rams started effectively using crossing routes against Slay. 

In the second quarter, Woods had Slay badly beaten, but pressure from Devon Kennard caused an errant throw and incompletion. Later in the quarter, Woods bested Slay again, resulting in a 8-yard touchdown. Early in the third, Woods netted 23 against Slay running a similar route. 

Finally, at the end of the third quarter, it was Josh Reynolds getting the better of Slay on a crossing pattern, but Goff misfired wide on the target. 

Combine results aren't everything, but it's the easiest way to compare player speeds. Slay ran a 4.36 coming out of college. Woods and Reynolds ran 4.51 and 4.52, respectively. Given that, it's becoming easier for me to believe Slay is hampered by a balky knee. 

Finding cracks

One of the brightest spots on Detroit's roster is the continued performance of the interior defensive line against the run. Damon Harrison and A'Shawn Robinson were largely excellent against the Rams, but Sean McVay's reputation as a play-caller came through in a big way with three runs right up the guy, which netted 43 yards and a touchdown. 

The first two plays were nearly identical. 

With Harrison lined up in 3-technique, between the right guard and tackle, the Rams left him unblocked on the snap, with the right guard, pulling left to wall off Robinson, the backside defensive tackle. Harrison took a step in toward the quarterback, but as Goff reached to his right to hand off to running back Todd Gurley, Harrison looked to change direction only to be blindsided by a wham block from tight end Tyler Higbee, coming inside from off right tackle.

Center John Sullivan shot into the second level at the snap to body linebacker Christian Jones, lined up behind Harrison, while right tackle Rob Havenstein sealed Kennard outside, leaving Gurley with a big hole and a one-on-one matchup with Slay in the second level. The cornerback made the stop, limiting the damage to 9 yards. 

Ten snaps later, the Rams ran the play again, and Ricky Jean-Francois, filling in for Harrison, fell for the same trap. Making matters worse, Slay missed the tackle, resulting in Gurley gaining 21 yards. 

Gurley's 13-yard touchdown in the fourth quarter also went to Harrison's gap, but it was hardly the nose tackle's fault. The Rams included end around play-action in the design, which drew the pursuit of two defenders behind Harrison, while Havenstein drove the edge defender to that side wide, creating an impossible lane for Harrison to defend. 

As for Gurley's game-sealing run late in the fourth quarter, the blame for not stopping that one falls on Ziggy Ansah. He had a shot at the line, but was overpowered by a jarring punch from guard Rodger Saffold, which caused the former Pro Bowler to lose his footing and his gap.

 Human cheat code

Aaron Donald is the most dominant player in football and the talk of him being the league's MVP is fully warranted. As someone who watched Ndamukong Suh on film every week, and saw plenty of game-changing performances, he was never as impactful as Donald was on Sunday. 

Utilizing a perfect combination of speed, power and anticipation, Donald made Detroit's interior lineman look like children on more than a dozen snaps. The NFL sack leader uses his hands like a world-class martial artist, leaving rookie guard Frank Ragnow and backup Kenny Wiggins flailing in a phone booth.

More: Lions' Ragnow can learn after being schooled by Rams' Donald

Donald won with swim moves to the inside and bent around the outside shoulder of the guards like an elite defensive end. 

Single team, double team, it didn't matter. He finished two sacks, had another one wiped out by penalty, forced a fumble, tacked on two more tackles in the backfield, delivered a hit on Stafford that saved a touchdown and had several other pass disruptions. 

A creative outlet

It was nice to see the Lions get creative with the offensive game plan, given the glaring talent deficiencies the team is trying to overcome right now. Some of those plays worked, others not so much. 

The shovel pass to Bruce Ellington on 3rd-and-2 in the red zone was a decent call, but, for one reason or another, defensive end Dante Fowler was left unblocked on the play. Ragnow pulled that direction, and had the ability to put a body on Fowler, but didn't. Difficult to imagine the execution matched the design here. 

The double-pass for Ellington was a train wreck. Stafford skipped the initial throw, the blocking didn't hold up and Kenny Golladay, the play's primary target, was never open. 

What did work was the usage of Levine Toilolo. I'm not sure if it was part of the plan coming in, or a mid-game adjustment, but the Rams were clearly not acknowledging Toilolo as a downfield threat, having their safeties consistently staying wide to support the outside cornerbacks. That led to gains of 22 and 39 yards for the tight end down the seam. 

And the touchdown pass to left tackle Taylor Decker was set up well throughout the game, with the Lions regularly rotating in Joe Dahl (loved the way he handled some fullback work, by the way) and Tyrell Crosby, leading to a steady stream of announcements that No. 66 and No. 65 were eligible. Then, when in the red zone, as the crowd got loud, the Rams were likely caught off guard by Deckers' 68 being listed as eligible. 

The design worked well because Detroit overloaded the right side of their formation, forcing Los Angeles to compensate. Finally, Golladay, the lone receiver to the left, ran a shallow crossing pattern, drawing away the remaining defender from play side.

Twitter: @justin_rogers