Raiders rookie cornerback Dexter McDonald, a seventh-round pick, was the only new absence at Sunday’s practice, the team’s first in pads.

Tight end Clive Walford still didn’t practice, but was seen working out on the side, and running back Trent Richardson and wide receiver Rod Streater remain on the non-football illness list.

Coach Jack Del Rio said Richardson and Streater are both at camp, but they haven’t been seen on the practice field. When asked if Richardson’s absence could affect his ability to make the team, Del Rio praised his conditioning.

“He’s down in the low 220s and that what we asked of him,” Del Rio said. “That’s where he was as a player at ‘Bama. I really believe with him committing himself like that and getting himself in that type of shape that he’ll have a chance to come out here and show what he’s really capable of.”

When Richardson was cut from the Indianapolis Colts in March, his weight was believed to be an issue. His placement on the non-football illness list indicates he’s not injured so much as he may be sick. What kind of illness that may be, nobody quite knows, but Del Rio’s comments make it seem like he’s doing well physically.

* Michael Crabtree continued to be among the team’s standouts at practice with a couple more nice catches. Running back Michael Dyer, whose repetitions in practice are boosted by Richardson’s absence, also had a nice day.

Dyer broke a long touchdown run during 11-on-11 work, getting some nice blocking off the left side before burst down the sideline.

“I think Michael’s done a nice job developing,” Del Rio said of Dyer. “From what we saw in the spring to where he is now, he’s more comfortable, he’s more accountable, he’s more dependable. Every now and then, he’ll pop through there and show some of the speed he has.”

Dyer’s long run came after the first- and second-team offenses both went three-and-out during that team portion toward the end of practice. One of those possessions ended with a blocked punt.