Where does Ian Willams’ contract rank among interior defenders?

Advanced statistics site Pro Football Focus ranked the five best interior defender contracts on Tuesday, which lists the five most team friendly contracts at that position – excluding rookie contracts. San Francisco 49ers nose tackle Ian Williams came in as the second best in the league.

In March, Williams, who was about to become a free agent, agreed to a new five-year contract with the 49ers. That contract was believed to pay Willians between $5 and $6 million per year. However, when his availability for the 49ers' season opener in September came into question, that contract was replaced by a one-year deal.

Following a physical, it was determined that Williams' rehab from surgery on his left leg would require more time that originally believed. The base salary on his new deal is $1 million with bonuses that bring the cap hit for the 49ers to $4 million. The contract allows the 49ers to evaluate Williams for another season, but will once again make him a free agent in 2017. Prior to the extent of the injury becoming better known, Williams was considered one of the top interior defender free agents.

Williams missed 21 of 32 games from in 2013 and 2014 because of a leg fracture in each of the two seasons. He became a starter in 2014, but the fractured leg ended his season after nine games. He started all 16 games for the 49ers in 2015 and underwent a follow-up procedure upon completion of the season.

"The 18th-highest-graded interior defender (85.6) in the league last season, Williams was a bright spot in an otherwise down year for the 49ers," explains Eric Eager of Pro Football Focus. "Having played just 271 snaps in his first four seasons, Williams emerged as a dominant force against the run, finishing last season with the ninth-highest run-stop percentage (10.6) among defensive tackles (tied with Linval Joseph). He finished the year particularly strong; his run defense grade over the last six weeks of the season was third among defensive tackles, with his overall grade being fourth. He added a respectable 19 pressures as a pass-rusher, as well."

While he did have an 85.9 overall grade last season according to Pro Football Focus, Williams had a slightly higher 89.0 run-defense grade, which ranked 11th-highest among interior defenders, and was in on 379 running snaps versus 298 passing snaps.

Williams' $4 million cap hit ranks 19th among defensive tackles and is in the same range as Lions DT Haloti Ngata and Jaguars NT Roy Miller. That number also ranks seventh on the 49ers.

Williams joined the 49ers as an undrafted free agent out of Notre Dame in 2011.

Ian Williams' contract at a glance
Signed through: 2016
Base salary: $1 million
Cap hit per year: $4 million

* Cap numbers from Spotrac.com