With a defense nearly void of any true playmakers, shipping off one of the few that could create turnovers didn’t make too much sense.
As more details came out, there appeared to be more beneath the surface as to why Detroit general manager Bob Quinn parted ways with Diggs, a team captain. But, that’s neither here nor there right now.
Recently, Mina Kimes of ESPN stated, “I know people were confused by the move (the Diggs trade) at the time, but I feel like it deserves even more criticism!”
Citing the Lions' severe statistical defensive decline not long after sending Diggs to the Seattle Seahawks, Kimes appears to be under the impression that the loss of Diggs had plenty to do with the Lions’ afflictions.
Now, there is definitely some truth -- or a major coincidence -- that the Lions' defense went from below-average to rock-bottom from Week 7 on. However, it’s hard to completely place all of the defensive issues solely on the departure of Diggs.
First off, Diggs was struggling with the Lions in 2019.
Before leaving Detroit, he was tied for the most missed tackles on the team, had no pass breakups, no interceptions, no forced fumbles and zero quarterback pressures.
He just didn’t seem to be his usual ball-hawking self.
It’s not like his 53.6 Pro Football Focus coverage grade with the Lions was carrying their secondary.
Oddly enough, Diggs didn’t even play in the Lions' first matchup with the Green Bay Packers, and only played 13 snaps against the Kansas City Chiefs in Week 4 due to injury.
The Lions held both Aaron Rodgers and Patrick Mahomes somewhat in check during those weeks.
Mahomes had his second-lowest passer rating on the year, and it was his only 2019 game without a passing touchdown.
Meanwhile, Rodgers had a modest -- at least for the Lions' defensive standards -- 90.0 rating against a Diggs-less defense in Week 6.
When Diggs did heal up to play in his final game in Honolulu Blue in Week 7 against the Minnesota Vikings, the Lions' defense allowed a passer rating of 141.5 to Kirk Cousins -- the highest single-game rating allowed by Detroit’s defense all season.
For whatever reason, the Lions still were decent when Diggs was out due to injury in the first half of the season.
They really fell apart in the second half of the year, and that just so happens to coincide with the time when Diggs left town.
As for another theory, it also wasn’t too long after Diggs went to Seattle that Detroit quarterback Matthew Stafford went down with a back injury.
The Lions' offense averaged almost a full two minutes more a game on the field with Stafford.
Not to mention, sans Stafford, the Lions' defense had to deal with worse average starting field position.
Yes, trading Diggs probably didn’t help the Lions' defense.
But, you can’t definitively say it was the catalyst to the Lions' defensive problems, either.
Overall, there are just too many variables in play to juxtapose a before-and-after scenario based off one individual.