Yellow flags, a missing All-Pro, and an inexperienced rookie who got taken to school are three of the reasons the Eagles lost to the Cowboys on Sunday and have missed the playoffs for the first time since 2016.

Let’s take a closer look at five reasons why the Eagles lost:

The penalties

The Eagles committed 12 penalties for 115 yards Sunday. That was the most flags they’ve drawn in a game since 2016 and their most penalty yards since 2017.

Eight of the 12 penalties were pre-snap, including six false starts and an inexcusable delay of game. The Eagles have 13 false starts in the last three games since Jalen Hurts became the starting quarterback.

Doug Pederson acknowledged after the game on Sunday that the false starts are linked to the cadence difference between Hurts and Carson Wentz, though it really shouldn’t be this big of a problem in empty and partially-filled stadiums.

Right tackle Matt Pryor had three of the six false starts against the Cowboys. Left guard Isaac Seumalo had two, and tight end Zach Ertz had the other.

Pryor’s first false start, in the second quarter, came on a third-and-9 at the Dallas 35. It not only killed the drive, but also took the Eagles out of field-goal position.

With the Eagles trailing, 30-17, Darius Slay’s third-quarter interception gave the Eagles a first down at the Dallas 28 with a chance to shift momentum. But a hold on Pryor, followed by false starts by Ertz and Seumalo blew a golden opportunity for the Eagles to get back into the game.

Missing Fletch

Often times, the best way to understand a player’s importance to a team is to see how it plays without him. Fletcher Cox played just seven snaps Sunday against the Cowboys before leaving the game with a stinger, and the defense was lousy without him.

A pass rush that already was missing edge rushers Derek Barnett and Josh Sweat struggled mightily without six-time Pro Bowler Cox. They had just one sack after he got hurt in the first quarter, and that came with five minutes left in an already-lost game. Without Cox next to them, the Eagles’ other two D-tackles – Malik Jackson and Javon Hargrave – had one total quarterback pressure between them. One. Against a very ordinary Cowboys interior offensive line.

Cox turned 30 earlier this month. His salary cap number is going to jump from $17.1 million to $23.9 million next year. Sunday showed just how valuable he is to Jim Schwartz’s defense. Not just as a pass rusher, but also as a key to their run defense. Ezekiel Elliott notched just his second 100-yard rushing performance of the season against the Eagles, rushing for 105 yards on 19 carries. He averaged 7.0 yards per carry on first down Sunday.

The Eagles had held their previous five opponents to 3.9 yards per carry. The Cowboys averaged 4.4. In the last four games, they had held teams to 3.3 yards per carry on first down. On Sunday, the Cowboys averaged 5.3.

Tough day for Jacquet

Last week, rookie Michael Jacquet drew positive reviews for the way he battled Cardinals wide receiver DeAndre Hopkins. Hopkins had nine catches for 169 yards and a touchdown, many of them against Jacquet. But he made Hopkins work for most of it.

On Sunday, even with Darius Slay back in the lineup, Jacquet struggled mightily. Cowboys quarterback Andy Dalton went after him right from the start. By my count, he gave up six catches for 175 yards, most of them to Cowboys wide receiver Michael Gallup. He also was called for a 26-yard pass-interference penalty on the Cowboys’ first scoring drive while trying to cover Gallup.

Jacquet gave up a 14-yard completion to Gallup on a third-and-9 on the Cowboys’ second scoring drive. He was late reacting to a screen to Gallup in the second quarter, then got blocked by Amari Cooper, which allowed Gallup to run 55 yards and set up a Greg Zuerlein field goal.

On yet another Cowboys scoring drive late in the second quarter, he gave up a 19-yard sideline toe-tapper to Gallup and, on the very next play, a 7-yard touchdown pass to Gallup with just 16 seconds left in the first half that gave Dallas the lead for good.

Things didn’t get any better in the third quarter. Matched up against Cooper on a second-and-5, he got beaten on an inside move and slipped. Cooper caught a quick pass from Dalton and took it 69 yards to the Philadelphia 4-yard line.

Jacquet wasn’t the only Eagles cornerback who struggled Sunday. Nickell Robey-Coleman, who has not had a very good season since signing a one-year free-agent deal with the Eagles in the offseason, got beaten by Cowboys rookie CeeDee Lamb on a wheel route for a 52-yard touchdown in the third quarter that gave Dallas a 27-17 lead.

First-down defense

The Eagles were ninth in first-down defense through their first 14 games, holding opponents to 5.1 yards per play. In their Week 8 win over the Cowboys, with Ben DiNucci at quarterback, the Eagles held them to a season-best 3.6 yards per play on first down.

Things were much different Sunday with Andy Dalton at quarterback. The Cowboys averaged 8.7 yards on first down. That’s the highest first-down average against Schwartz’s defense this season.

Elliott averaged 7 yards per carry on first down. Dalton was 12-for-13 for 175 yards and a touchdown on first down.

The Cowboys’ success on first down set up too many third-and-shorts. Ten of Dallas’ 13 third-down opportunities, including 7 of their first 9, were 4 yards or less. They converted 6 of their first 9 third-down opportunities as they built a 10-point lead.

Dalton’s 52-yard touchdown pass to Lamb in the third quarter, which put the Cowboys up, 27-17, came on a third-and-3.

» READ MORE: Jalen Hurts vs. Carson Wentz: It’s a competition after Eagles’ 37-17 loss to Cowboys | Marcus Hayes

No finishing touch

For the first time since 2017, the Eagles scored touchdowns on their first two possessions. They had a season-high 477 yards in total offense. They averaged a season-high 6.7 yards per play. They had 151 rushing yards. Jalen Hurts threw for 342 yards, the second-highest total by an Eagles quarterback this season (Carson Wentz had 359 in Week 7 vs. the Giants).

And yet, after those first two TD drives, the Eagles were able to score just three more points. They were in Dallas territory on seven of their last 10 possessions and scored three points.

Sure, the pre-snap penalties played a role. But there were other factors. Hurts, who completed 9 of 14 passes in the first half and averaged 12.7 yards per attempt, was 12-for-25 for 164 yards with three turnovers in the second half. His red-zone interception with seven minutes left in the game was the Eagles’ death knell

Hurts is quickly learning stuff about the NFL, including that players at this level are pretty good at stripping the ball from you, no matter how hard you’re squeezing it. He’s also learning that the difference between college coverages and NFL coverages is the difference between fifth grade and MIT grad school.

The Eagles converted 5 of their first 7 third-down opportunities, then were 2-for-10 the rest of the way. Hurts and Miles Sanders rushed for 93 yards on 16 carries in the first half, then gained just 33 yards on eight rushes in the second half.

The Eagles used a lot of 12-personnel packages to help Matt Pryor with DeMarcus Lawrence. But left tackle Jordan Mailata struggled with the Cowboys’ other edge-rusher, Randy Gregory. Gregory beat him on a third-and-3 play in the third quarter and forced a throwaway. On the Eagles’ next possession, Gregory beat him again for a 13-yard sack right after Hurts had completed a 43-yard pass to Quez Watkins at the Dallas 32.

» READ MORE: Eagles offense finally starts strong, then collapses in costly loss to Cowboys