K’Waun Williams an unsung hero for 49ers in 2019

The San Francisco 49ers have some cornerback needs heading into 2020, but nickel corner isn’t one at all, thanks to what K’Waun Williams did last season.

San Francisco 49ers cornerback K’Waun Williams will remain with the team for yet another season, according to a Thursday report from The Athletic’s Matt Barrows, citing Williams’ agent.

The Niners not shockingly picked up Williams’ option for 2020, ensuring the 28-year-old defensive back would be back with the team amid some notable concerns about the secondary heading into the offseason.

Addressing the secondary is high atop San Francisco’s offseason to-do list, yes. But worrying about the nickel cornerback spot isn’t part of those worries.

Williams, whom the 49ers picked up as a free agent back in 2017, was exceptional last season. While the traditional stats look relatively pedestrian — 54 tackles, a sack off a blitz, two interceptions and two passes defended — it’s hard to overlook what the 5-foot-9 defensive back did to ensure opposing quarterbacks didn’t target him in coverage.

Among nickel cornerbacks who played at least 50 percent of 563 coverage snaps in 2019, Williams allowed an opposing passer rating of just 73.9, which ranked second best among qualifiers in this category, according to Pro Football Focus. Additionally, Williams’ 0.94 yards allowed per snap ranked fourth best among this same group, too, showcasing just how valuable he was to a 49ers defense, which finished the year ranked best against the pass.

No wonder PFF ranked Williams its seventh best cornerback in the league in 2019, and that’s not just among nickel corners, either.

While boundary cornerbacks often receive the most amount of attention — and money, to argue the point — nickel defensive backs are becoming increasingly valuable to team defenses. In 2018, teams employed nickel defenses 60.5 percent of the time, according to Football Outsiders, and one figures that number to have stayed close to the mark in 2019.

Especially in what has turned into a pass-first league.

Because of this, nickel backs have essentially turned into starters, seeing the same number of reps as the boundary corners. And one could argue a nickel cornerback’s job is much more difficult, guarding against more complex interior routes and not always having the sidelines to use as essentially another defender.

It’s reassuring to know Williams has been about as good a lockdown defensive back during his three-plus seasons with the 49ers, preventing most of the upper-echelon slot wide receivers from doing damage against San Francisco in recent years.

And with Williams still young and under contract, the Niners don’t have to worry about this position being a liability at all heading into 2020 and likely beyond.