Going back and watching the film of Sunday's overtime loss against the Tennessee Titans was difficult because of all of the missed opportunities on both sides of the ball. The Eagles had chances to put the game out of reach early and finish it late, but just couldn't execute enough on offense and defense in key spots. I detailed my findings from watching the offense on Monday night, so now it's time to look at what happened on defense.

The biggest story coming out of this game is the breakdowns in coverage, and I'm going to cover some of what happened in the secondary. It was not one specific thing that popped up time and time again, as is always the case in football, rather a few different issues. Poor discipline and awareness in zone coverage, getting beaten in man-to-man situations, bad tackling, bad execution in rush lanes up front, and just flat-out good play design from the offense all led to some big plays against this Eagles defense in key moments, particularly in the fourth quarter and in overtime. To start off this piece, however, I want to talk about Cover 3, one of the staple coverages of Jim Schwartz's defense, and why there were some adjustments off of that in this game.

The more you study football, the more you realize how much the front impacts the coverage, and vice versa. There are examples of it in every game, whether they are on individual plays or in overall game plans and defensive philosophies.

What do we know about Jim Schwartz and this Eagles defense? It all starts with an aggressive four-man rush, right? Those guys are flying upfield. They want to live on the other side of the line of scrimmage and wreak havoc. Complementing that, the linebackers are also aggressive. Those guys fly downhill, attacking the run game. The Eagles are a "fast-flow" team, reacting to the first thing they see like sharks smelling blood in the water. That aggressive nature, in my opinion, is the right way to play defensive football, and it helped them win a title a year ago.

Going into this game against the Titans, who ran the ball more than any team in football (particularly on first down), the Eagles were going to need to play a lot of single-high coverage. The Eagles are primarily a single-high safety team anyway. That means you play with a true free safety in the middle of the field (in this game, it was Corey Graham) and a strong safety closer to the box (for three years in this scheme, that's been Malcolm Jenkins). When you play single-high zone coverage, you are playing, in some way, shape, or form, Cover 3 zone.

Cover 3 is played at every level of football. You have four underneath zone defenders spread out across the width of the field. Three deep players account for the vertical part of the field. In the most basic terms, that is Cover 3.

Now, keep in mind, every player on every snap has a pass responsibility and a run responsibility. All four of those underneath zone coverage defenders must make their presence known in the run fit before they decide to drop back in zone coverage. That must happen first. Play the run, then turn and find your landmark in zone coverage.

Titans offensive coordinator Matt LaFleur knows this. He comes from the Kyle Shanahan coaching tree, where he also worked with Sean McVay. That system is predicated on getting teams to play in these single-high looks on a weekly basis, establishing a strong run game, and then hitting them both down the field and in the intermediate area of the field off play-action. We saw this with Jake Plummer in Denver, Robert Griffin III in Washington, Matt Schaub in Houston, Matt Ryan in Atlanta, and now Jared Goff in Los Angeles as well as in San Francisco with Jimmy Garoppolo before he was injured. That is in the DNA of this offensive game plan, to attack teams off play-action and put the linebackers in a bind. Last Thursday night, McVay and his Rams abused Minnesota and their two stars in the middle of this defense, Eric Kendricks and Anthony Barr, with the same principles. Against Cover 3, this offense can do some real damage.