PFF's cornerback rankings show how far Chargers' J.C. Jackson has fallen

For as much as the LA Chargers struggled defending the run last season -- they surrendered the fifth-most rushing yards and most rushing touchdowns of any team -- their pass defense really held its own.

For the year, the Chargers allowed the seventh-fewest pass yards and seventh-lowest completion percentage against the pass. Incredibly, they accomplished that largely without help from J.C. Jackson, their prized free agent acquisition who was widely pegged as one of the best signings of any team.

At the same time, though, there was wide contingent of Chargers fans who viewed the Bolts' commitment to Jackson as a big overpay.

Was he a product of Bill Belichick's system? Would he enjoy similar success covering opposing team's No. 1 receivers in a new scheme? Those were just some of the reservations that were exercised when the deal was made.

After one season, it goes without saying those reservations were justified. Widely regarded as a top-five cornerback heading into 2022, Jackson didn't even make Pro Football Focus' rankings of the top 32 corners in the league.

Chargers' J.C. Jackson left off PFF's 2023 cornerback rankings

For context, Jackson landed in PFF's "elite" tier going into last season. In order, the first tier comprised Jalen Ramsey, Jaire Alexander, A.J. Terrell, Jackson, Marshon Lattimore, Darius Slay, Xavien Howard, Tre'Davious White and Marlon Humphrey.

Here's what PFF said then about Jackson:

"The former Patriot ranks second in man coverage grade since 2018. He has intercepted 19 passes in man coverage over that span — five more than the second-place player and twice as many as third place. His mirror ability and poise at the catch point make him a nightmare to throw at."

That analysis is a distant memory for Chargers fans. Jackson underwent season-ending knee surgery after five games -- just months after he went under the knife in August to repair an ankle injury -- but he was a shell of the player he was with the Patriots before the knee injury.

In those five games, Jackson allowed 19 catches on 27 targets (70.4% completion percentage) for 370 yards and four touchdowns, per PFF. Further, he allowed 19.5 yards per reception, a 154.2 passer rating and was penalized three times.

It really doesn't get much worse than that.

Luckily, one year doesn't make Jackson a bust signing. The pre-season ankle surgery wasn't ideal and the knee surgery ruined any chance he had to make up for his slow start.

Assuming he's fully healthy going into the new campaign, Chargers fans should expect a much-improved Jackson. PFF's cornerback rankings aren't an indictment on him as a player. They just reflect that everything that could go wrong, did go wrong for the 27-year-old.