Dallas Cowboys: Let’s talk about Trevon Diggs

Yards

With a heading titled “Boom or Bust,” Monson lists some basic volume stats. For the sake of his argument, the important ones to note are receptions allowed (53), yards allowed (962), and touchdowns allowed (5). (According to PFF, Diggs has the fourth-highest, tenth-highest, and ninth-highest numbers in the league) These numbers vary depending on who calculates the statistics, but the numbers themselves are roughly similar.

Monson makes it a point to say Diggs could surpass “catastrophic liabilities in coverage” in yards allowed in a season, which is true. He mentions how the Kansas City Chiefs targeted him ten times and the New Orleans Saints eight times even with his propensity to catch passes near him. In all fairness, Diggs allowed 11 receptions in these two games so this does show that no matter the strength of the QB, targets end up his way.

Only that’s the case for A LOT of good cornerbacks. AJ Terrell, an undisputed All-Pro talent this season, has been 56 times according to PFF. (That number feels suspect given PFR has 74 targets) Jalen Ramsey? 83 times. Darius Slay? 70 times. Marshon Lattimore? 87 times. Kenny Moore II? 107 times!

Being a good cornerback doesn’t shut down targets coming to your side of the field. Passing offenses are progressed immensely from the days of “Revis Island” that even if a cornerback may look the part of a “shut down cornerback” he will inevitably get targeted in the natural flow of the offense.

Obviously, this means what happens when he gets targeted is what’s noteworthy. So what gives?

Diggs does give up a lot of yards per reception, but it happens because his average depth of target is decently high. But it isn’t an outlier compared to the other cornerbacks mentioned.

Trevon Diggs:  10 Yards
A.J. Terrell: 8.9 Yards
Jalen Ramsey: 7.9 Yards
Darius Slay: 10.6 Yards
Marshon Lattimore: 13.3 Yards
Kenny Moore II: 7.3 Yards

With the exception of Kenny Moore II because he’s a nickel cornerback, Diggs’ average depth of target is near the average of the cornerbacks seen as the best at their position. Unlike them, Diggs just allowed deeper passes as their average yards per completion is noticeably different.

Trevon Diggs:  16.4 YPC
A.J. Terrell: 9.8 YPC
Jalen Ramsey: 9.3 YPC
Darius Slay: 10.4 YPC
Marshon Lattimore: 14.7 YPC
Kenny Moore II: 9.3 YPC

So it’s incredibly obvious Diggs’ receptions tend to bleed the Cowboys’ defense a bit more. This isn’t a result of prevent or soft zone defenses either as Monson points out.

"Dallas is obviously a good team this year and often plays with a lead, but those coverage numbers aren’t simply a product of playing soft zone coverage with the game in hand. In fact, Diggs leads the league in yardage allowed in the first quarter, and the first three quarters, not just overall. He ranks 98th out of the 100 corners who have played 100 or more snaps at outside corner in yards allowed per coverage snap. The Alabama product has also allowed five touchdowns. The simple fact is that when he does give up a catch, it tends to be a big play. The average catch allowed in Diggs’ coverage this season has gone for 18.2 yards, with around 40% of that coming after the catch. Dallas is obviously a good team this year and often plays with a lead, but those coverage numbers aren’t simply a product of playing soft zone coverage with the game in hand. In fact, Diggs leads the league in yardage allowed in the first quarter, and the first three quarters, not just overall. He ranks 98th out of the 100 corners who have played 100 or more snaps at outside corner in yards allowed per coverage snap. The Alabama product has also allowed five touchdowns. The simple fact is that when he does give up a catch, it tends to be a big play. The average catch allowed in Diggs’ coverage this season has gone for 18.2 yards, with around 40% of that coming after the catch."

Monson’s point about the YAC (yards after catch) Diggs concedes felt fairly irrelevant as Terrell, Ramsey, and Moore II give up a higher percentage of YAC than the former Crimson Tide cornerback. As for his other argument, there isn’t much of a rebuttal because he correctly disposes of a narrative that likely gets spread with Diggs.

But something that Monson pretty clearly neglected within his argument is Diggs completion percentage. PFF has the second-round pick’s completion percentage at 57 percent. Here are the others:

A.J. Terrell: 42.9%
Jalen Ramsey: 65.4%
Darius Slay: 59.4%
Marshon Lattimore: 56.3%
Kenny Moore II: 67.9%

If we give the quickest of glances at this information, it’s incredibly clear that Diggs’ completion percentage is in the ballpark of these guys while being targeted more often than all of them! It doesn’t take a 160 IQ to make the easy statistical inference that he’s preventing completions at a rate similar to some of the “best” cornerbacks in the league.

Surely we can establish a trade-off between this and yards allowed and how it helps the Cowboys maintain the top defense according to defensive DVOA. But onto greater problems…