ALAMEDA — Malcolm Smith may not be the Raiders’ most indispensable defensive player, but you’d never know it by the participation chart.

When the opponent has the ball, Smith can be found in the middle of things, hardly ever on the sideline.

Over the past seven games, Smith hasn’t missed a single snap on defense and has been off the field for only eight plays in 13 games.

“I come from a place where I was starving for snaps. Now I get a ton of ’em,” Smith said Tuesday. “It’s awesome — a responsibility I am embracing,”

Signed as a free agent from the Seattle Seahawks, the former Super Bowl XLVIII Most Valuable Player following the 2013 season often found looking for scraps in 2014 as the linebacker-rich Seattle Seahawks played Bruce Irvin, Bobby Wagner and K.J. Wright.

When defensive coordinator Ken Norton Jr. arrived from Seattle as the defensive coordinator, it wasn’t long into free agency that Smith joined him. On March 11, the same day the Raiders announced the signings of center Rodney Hudson, linebacker Curtis Lofton and tight end Lee Smith, they also signed Smith.

Smith leads the Raiders with 115 tackles, is second to Khalil Mack with four sacks and also has nine passes defensed, an interception and a forced fumble. In a defensive unit that does a lot of substitution, Smith has played 99.1 percent of the snaps.

The only player who is close is safety Charles Woodson (900 of 928, 97 percent), the Raiders’ second-leading tackler.

While Lofton was brought in to be the middle linebacker, it has been Smith, 6 feet, 225 pounds, who emerged as the signal caller in radio contact with Norton.

Linebackers have rotated like satellites around Smith since the season began. Former starters Aldon Smith (suspension) and Ray-Ray Armstrong (waived) left the roster, replaced by rookie draft picks Neiron Ball and later Ben Heeney. Ball was placed on injured reserve with a knee injury. Lofton, who does his best work on run downs and sometimes has difficulty in coverage, has been off the field for more than 40 percent of the snaps.

“It’s a challenge at times because you’ve got to develop a rapport with each guy, but our group has done a good job of sticking together and trying to learn from each other’s mistakes,” Smith said. “I think we’re going to continue to develop, and getting those young guys experience makes us stronger as a group.”

While the Seahawks were fairly straight up defensively and dared offenses to beat their talent, Norton and coach Jack Del Rio have tinkered with the Raiders’ schemes all season, mixing alignments and coverages, hoping to get the best mix.

“It’s been a process throughout the year,” Smith said. “We’ve been able to adapt in certain situations and in some others we didn’t perform as well as we planned to. Obviously you want to put your guys in the best position to make plays. I think that’s why we’ve altered things the way we have and lately the results have been pretty good.”

The Raiders hit a two-game rough patch against the run in early November as Pittsburgh and Minnesota combined for 458 yards with big days from DeAngelo Williams (170 yards) and Adrian Peterson (203). In the past four games, the Raiders have given up 276 yards and 3.0 yards per carry.

“We take pride in that part of our game, and in those two games it showed up as a weakness. We had to get better at it”

The Raiders signed long snapper Thomas Gafford and placed Jon Condo on season-ending injured reserve with a shoulder injury. Gafford, 32, was the long snapper for the Kansas City Chiefs from 2008 through 2014 and spent part of training camp this season with the Chicago Bears.

Starting and reserve offensive linemen were surprised to find 55-inch flat screen color televisions in front of their lockers following practice as gifts from quarterback Derek Carr.