The Ravens haven't started negotiations with nose tackle Brandon Williams, but that will change soon with free agency about to start in six weeks.

Williams was already the team's top priority to re-sign, but he became even more important last week when inside linebacker Zachary Orr, the team's leading tackler last season, announced his retirement because of a congenital neck/spine condition.

Without Orr, the Ravens defense is weaker. Without Williams and Orr, the Ravens would have no interior presence. So when contract talks begin, the Ravens have to ante up and pay Williams big dollars.

There is little choice now.

The Ravens' only real strength in 2016 was their run defense, and even that collapsed in the final four games of the regular season. Despite the drop-off, the Ravens allowed only 89.4 rushing yards per game — fifth best in the league.

The foundation is in place for the Ravens to take the next step in 2017, but the team has to start by bringing back Williams, who is eligible to become an unrestricted free agent March 1.

All great defenses are built around stopping the run first and forcing the opposition into low-percentage passing situations. The Ravens had trouble doing that without Orr in the last game of the season against Cincinnati, and they can't do it without Orr and Williams.

Defensive tackle Michael Pierce had a strong season as a rookie last year, but he isn't in Williams' class yet. Williams, a fourth-year player out of Missouri Southern State, is at the peak of his career and plays a position at which players don't usually last long.

In 2015, Williams set career highs in tackles (53), solo stops (35), sacks (two) and passes defended (two). In 2016, he practically matched that production, despite being constantly double-teamed because opposing teams knew he was the key to the run defense.

Williams, 6 feet 1, 335 pounds, has a presence in the locker room that sets him apart, too. He became the leader of the defensive line, and had a large role in the development of Pierce.

After a tough loss, it was either Williams, safety Eric Weddle or outside linebacker Terrell Suggs whom the media went to for answers. Williams never backed away.

The Ravens need him back.

It will be costly. This is the year for him to make the biggest and best deal of his career. He has shown his durability by starting in 48 of the team's past 50 games. As a third-round pick and the 94th player selected in the 2013 draft, Williams initially signed a four-year contract worth nearly $2.7 million.

His career earnings will soon increase exponentially.

The benchmark deal now for Williams' position is the five-year, $46.25 million contract signed by the New York Giants' Damon Harrison in March. Williams is going to demand at least that and probably more because of the increase in the salary cap.

It would be to the Ravens' advantage to sign Williams before the start of free agency, because he is going to command top dollar once he gets to the market. Williams, the father of two young children, likes life in Baltimore, but it would be to his advantage to test the market.

The Ravens know Williams' value. When the nascent team was struggling in the 1996 and 1997 seasons, general manager Ozzie Newsome swore he would acquire a massive defensive tackle. The Ravens eventually added two: Tony Siragusa and Sam Adams.

Newsome's philosophy has always been that a defense needs to be strong up the middle. Almost 20 years ago, Siragusa and Adams had to protect middle linebacker Ray Lewis. Last year Williams had to keep offensive linemen off inside linebackers C.J. Mosley and Orr.

But Orr is gone now. And without Williams, there would be less protection for Mosley. At this time, Williams' leverage is stronger than ever.

The Ravens have to find a way to bring him back, almost at any cost.

mike.preston@baltsun.com

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