In 2017 the Oakland Raiders pass defense was ranked 26th in yards allowed, 18th in touchdowns given up, 31st in completion percentage of opposing QB’s (68%. Ouch!), 28th in yards per completion, 24th in sacks, and dead last in interceptions with just 5 on the entire season last year. Clearly, they were beyond awful and desperately in need of improvements.
Considering those numbers a top priority in free agency and the draft should have been to upgrade the secondary. They replaced the cornerback trio of Sean Smith, David Amerson, and TJ Carrie with a stockpile of questionable cornerback talent and signed veteran journeyman safety Marcus Gilchrist.