Raiders expect big things from defensive tackle Mario Edwards Jr. The 280-pound defensive tackle is healthy right now, and the Raiders know they need him to make an impact for their 26th-ranked defense a year ago to get better. Edwards, after all, missed the first 14 games last season after a hip injury was slow to heal. Raiders head coach Jack Del Rio said after Tuesday’s workout, At the end of the day, we didn’t get a whole lot of Mario on the field. The Raiders are looking for a big step and a big push inside from Edwards, who played both tackle and end as a rookie in 2015. Edwards has worked on his explosiveness, doing a lot of squats and lower-body work in the weight room, plus running in sand. Outside linebacker Bruce Irvin often mentioned the lack of push from defensive tackles last season, and the Raiders were last in the league in sacks, despite having Irvin and Defensive Player of the Year Khalil Mack. “Just ready to do what Reggie already said, you know, to show that I’m ready to be a dominant player and pick up where I left off before I got hurt,” Edwards said. Running back Marshawn Lynch didn’t wear a helmet like the rest of his teammates at Tuesday’s workout, and then went to the weight room after running a couple of drills.