Cardinals coach Bruce Arians recently singled out last year's season-opening loss to the Patriots as the key to Arizona's disappointing 7-8-1 record in 2016.
Although Chandler Catanzaro took the brunt of the blame for a missed field goal in a two-point game, the kicker wasn't the lone culprit.
Filling in for a suspended Tom Brady, Patriots backup quarterback Jimmy Garoppolo succeeded in picking on rookie cornerback Brandon Williams for a 37-yard touchdown and a 28-yard completion that led directly to a second score.
That spot opposite six-time Pro Bowl selection Patrick Peterson would prove to be a liability several more times throughout the season.
Former Chiefs corner Marcus Cooper would eventually overtake Williams and parlay four interceptions into a three-year, $16 million contract with the Bears.
Now Williams is battling special teams ace Justin Bethel for the opportunity to wear a target on the back of his uniform for a second consecutive season.
"You should look forward to that opportunity. Coop got his four interceptions and got paid," Arians explained, via The MMQB. "There's no doubt that's one of the hardest jobs in the NFL, to play on the other side of Patrick. You've gotta have amnesia."
Quarterbacks tend to avoid Peterson, who shadows No. 1 receivers more often than any other defensive back in the league. That means the No. 2 cornerback in Arizona often ranks among the NFL's most frequently targeted.
For all of the personnel turnover on James Bettcher's defense this year, though, the Cardinals failed to bring in legitimate competition for Williams and Bethel.
Williams boasts all of the physical gifts to succeed in the NFL, but he's been playing the position for just two years after converting from running back in his final season at Texas A&M. While Bethel played meaningful snaps in big games two years ago, Arians quipped last December that the special teams ace's transition to starting cornerback was a "failure in progress."
Beyond its status as one of the toughest assignments in the league, the No. 2 cornerback opening is perhaps the most pivotal position for Arizona's playoff hopes in 2017.